Plant Productions - Articles List

Investigating integrated weed control on yield and yield components and qualitative traits of canola in rotation with corn

Negar Atashbar; Ali Monsefi; Esfandiar Fateh

Volume 47, Issue 1 , June 2024, , Pages 101-115

https://doi.org/10.22055/ppd.2024.43934.2106

Abstract

Introduction Conservation tillage practices and the presence of crop residues on the soil surface have a positive effect on crop yields by reducing the germination and establishment ... Read More Introduction Conservation tillage practices and the presence of crop residues on the soil surface have a positive effect on crop yields by reducing the germination and establishment of weeds during crop growth. The presence of weeds is one of the most important factors that reduce agricultural products in the world and it leads to a large reduction in the yield of agricultural products. Weeds, as one of the effective limiting factors for canola cultivation, cause a decrease in the yield of canola due to the competition in absorbing the environmental resources of growth such as nutrients, radiation, and water. On the other hand, mixing weed seeds with canola reduces the quality of its oil. Therefore, this experiment was conducted with the aim of investigating the integrated management of weeds and alternating plowing on the yield and some agricultural characteristics of canola in the conditions of Ahvaz. Materials and Methods In order to investigate the effect of sequential tillage and weed management, research was conducted in the year 2021-2022 in the research farm of the Faculty of Agriculture of Shahid Chamran University of Ahvaz, Ahvaz. The lay out of this research was an experimental design of split plots in the form of randomized complete block design with 3 replications. The main factor of tillage in three levels: 1) zero tillage-zero tillage, 2) reduce tillage-conventional tillage and 3) Conventional tillage-zero tillage and the sub-plot of weed control in six levels: 1) control, 2) hand weeding, 3) cycloxidem herbicide 2 liters per hectare in installments of 15 and 30 days after sowing, 4) cycloxidem herbicide 2 liters per hectare at 30 days after sowing, 5) crop residues as surface mulch (maize @ 5 tons per hectare) and 6) crap residues + cycloxidem herbicide was 1.5 liters per hectare at 30 days after sowing. Statistical analysis of data was done using SAS software and comparison of averages with LSD method. Results and Discussion The results of the experiment showed that the highest seed number per silique, the highest seed yield, the highest biological yield, and the percentage of oil in the treatment were related to the mutual effects of conventional tillage and manual weeding. The highest silique number per plant and 1000 seeds weight were in the conditions of conventional tillage and the application of 2 liters of herbicide per hectare in installments. The highest rate of harvest index was obtained with 26.80 percent in the condition without tillage and the application of 2 liters of cycloxidum herbicide per hectare in installments. Conclusion The use of conventional tillage and the use of cycloxidum herbicide 2 liters per hectare in division along with manual weeding can be effective in controlling weeds and increasing crop yield. In other hand the use of integrated management of weeds and the use of an effective combination of different methods of weed control with sequential tillage, which is effective in terms of society and the environment, and can reduce the damage caused by weeds and burning of residue.

Respose of corn growth and yield characteristics to different rounds of irrigation in the soil contains Apirus and Atlantis herbicide residues

Narges Saaedi; Kamal Hajmohammadnia Ghalibaf; Ali Ghanbari; Ebrahim Izadi Darbandi

Volume 46, Issue 4 , March 2024, , Pages 539-552

https://doi.org/10.22055/ppd.2024.44963.2126

Abstract

Introduction Maize (Zea mays L.) is an annual plant from the Poaceae family, which ranks third among crops due to its special characteristics, including a wide range of adaptation ... Read More Introduction Maize (Zea mays L.) is an annual plant from the Poaceae family, which ranks third among crops due to its special characteristics, including a wide range of adaptation in tropical and subtropical climates. In recent years, herbicides that inhibit the action of acetyl coenzyme A carboxylase and Acetolactate synthase have been widely used to control narrow leaves. One of the significant consequences of these herbicides being released into the environment is their persistence in the soil. This issue, along with the harmful effects on the activity of microorganisms and stability in the soil ecosystem, poses a serious threat to crop rotation, as their gradual leaching and runoff can lead to underground and surface water pollution. Materials and Methods This experiment aimed to investigate the residual effect of Acetolactate synthase inhibitor herbicides on some growth and yield characteristics of corn in different rounds of irrigation was conducted at Shadid Beheshti of Andimshek Agro-industrial Company in 2020-2021 and 2021-2022. The Acetolactate synthase inhibiting herbicides used in wheat were Atlantis herbicide (Mesosulfuron-methyl+ iodosulfuron-methyl-sodium, OD 1.2%, 1.5 L ha-1), Apirus herbicide (Sulfosulfuron, WG 75%, 26.6 g.ha-1), weedy check, and weed-free check as main-plot and different rounds of irrigation (one, two, three, and four rounds between wheat harvest to corn sowing) as sub plot were examined using a split-plot design with randomized complete block design with four replications. The investigated traits included plant length, number of leaves, ear length, ear diameter, number of rows per ear, number of seeds per row, 100 seeds weight, seed yield, biological yield, harvest index, and herbicide carryover in the soil. Results and Discussion The analysis of variance revealed that the application of herbicide and irrigation rounds significantly affected the assessed traits of corn. The highest values for plant length, number of leaves, ear length, ear diameter, number of rows per ear, number of seeds per row, 100 seeds weight, seed yield, and biological yield were observed in the weed-free check with four rounds of irrigation. The weedy check with one round of irrigation had the lowest values for these traits. Increasing the irrigation rounds reduced the negative effect of Acetolactate synthase inhibiting herbicides on corn plants, and Atlantis herbicide demonstrated a more destructive effect compared to Apirus herbicide. Examination of herbicide carryover in the soil indicated higher residues of Atlantis herbicide compared to Apirus herbicide, resulting in a more detrimental impact on corn plants. Conclusion Based on the results of this study, Apirus herbicide, with better weed control in corn fields and lower soil stability, had a less negative effect on corn plants compared to Atlantis herbicide. The findings from the two years of testing supported this conclusion. Additionally, it was observed that increasing soil moisture through more rounds of irrigation reduced herbicide carryover in the soil and consequently minimized their negative effects on corn plants. Therefore, based on the results of this experiment, it seems that in the rotation of wheat-corn, the use of Apirus herbicide in wheat cultivation to control weeds, as well as the implementation of a rounder irrigation method for corn, can lead to a better corn yield compared to the use of Atlantis herbicide. .

Evaluation of periods of interference and weeds control in chemical and organic nutrition management on yield and yield components of garlic

Reza Zahedipour; Aydin Khodaei Joghan; Ahmad Zare

Volume 46, Issue 1 , June 2023, , Pages 105-115

https://doi.org/10.22055/ppd.2022.40244.2017

Abstract

IntroductionGarlic (Allium sativum L.) as one of the medicinal plants has an important role in human health. Weeds control is very important to achieve optimal yield in agro-ecosystems. ... Read More IntroductionGarlic (Allium sativum L.) as one of the medicinal plants has an important role in human health. Weeds control is very important to achieve optimal yield in agro-ecosystems. The competitive ability relationship between plant and weeds is determined by the species' biological traits and environmental conditions such as space, light, water, and nutrient availabilities. Fertilizers play a significant role in the competition between crops and weeds in agriculture. Responses of weeds and crops to fertilizer application could be different, but many weeds tend to respond better than crop species to the high availability of nutrients. Also, the kind of fertilizer (chemical and organic) can affect crop-weed competition. Therefore, the purpose of this research was to evaluate interference and weeds control periods in the application of chemical and organic fertilizers on the yield and yield components of garlic in Ramhormoz climate. Materials and MethodsA factorial experiment based on randomized complete block design (RCBD) with three replications was carried out in Ramhormoz during 2019—2020 growing season. The first factor included nutritional management (chemical and organic) and the second factor included 12 treatments of interference and control period of weeds (0, 20, 40, 60, 80, 120 and 160 days). Chemical nutrition management includes the application of urea (46% application preplanting and after emergence) and Triple superphosphate (46% application preplanting) and Organic management, including the application of cattle compost and inoculation with Mycorrhiza. Results and DiscussionThe results of analysis of variance revealed that the effect of nutritional management on height of garlic wasn’t significant and on other traits garlic (Bulb diameter, bulb weight, Number of cloves per bulb, Biological yield and yield bulb) and weeds (narrow leaf dry biomass, Broad leaves dry biomass and Total weeds dry biomass) was significant. Periods of Weed Interference and Control weed treatments on all measured traits of garlic and weeds were significant. No interaction effects of nutrition and weed management treatments on the studied traits were observed. There was a significant difference between chemical and organic nutrition management, most of the yield traits and yield components of garlic were higher in organic application than chemical fertilizers. Also, the narrow leaf biomass, broadleaf, and total weeds in chemical application in comparison to organic fertilizers increased by 11.5%, 9%, and 10.5%, respectively. During the interval period for 120 days, garlic yield decreased by 100% and with the increase of control period (control in all growing seasons), bulb yield reached the highest value (3230 g.m-2). In weed control treatment for 20 days, bulb yield decreased by more than 86% compared to weed control treatment throughout the growing season. It seems that organic fertilizers with gradual release of nutrients could affect the competition of garlic with weeds, and by using organic fertilizers, the dry weight of weeds was less than chemical fertilizers. ConclusionThe results indicated that due to the presence of weeds and the poor competitive ability of garlic against weeds, the field must be controlled for a long time and the use of manure fertilizer for organic agriculture and increasing soil organic matter is recommended.

Chemical control of dandelion (Taraxacum sp.) weed in Kentucky bluegrass (Poa pratensis L.)

Seyedeh Maryam Mesbahi; Masoud Ghasemi Ghahsareh; Somayeh Esmaeili

Volume 46, Issue 1 , June 2023, , Pages 117-127

https://doi.org/10.22055/ppd.2023.41710.2055

Abstract

Introduction Dandelion with the scientific name (Taraxacum sp.) from the Asteraceae family is one of the common weeds of turfgrasses and pastures. Post-growth control of weeds in established ... Read More Introduction Dandelion with the scientific name (Taraxacum sp.) from the Asteraceae family is one of the common weeds of turfgrasses and pastures. Post-growth control of weeds in established turfgrasses is crucial and ignoring it severely damages the aesthetic aspect of turfgrass. Chemical methods are commonly used to control weeds in established turfgrass (Karimmojeni et al., 2012). The use of herbicides helps in the management of weed control in damaged turf fields along with non-chemical methods such as correct mowing height, effective irrigation, sufficient fertilization, and timely weeding. Perennial broad-leaf weeds can be selectively controlled with herbicides. U-46 Combi Fluid, Duplosan super, and Ioxynil are suitable herbicides for controlling broadleaf weeds in narrow-leaf fields. Materials and Methods In order to control the dandelion in Kentucky bluegrass turf, a factorial experiment was conducted based on a completely randomized design with 3 replications and 9 treatments in September 2022, at the green space of Shahrekord University. Replications included 1×1 m2 plots and the factors included two herbicides of U46-Combi Fluid and Duplosan Super and their interaction with Ioxynil. All selected plots were infested with dandelion weed. The treatments included U46-combi fluid at two levels of 1.5 and 2 L ha-1 (U1.5 and U2), Duplosan Super at two levels of 2 and 2.5 L ha-1 (D2 and D2.5), their interaction with Ioxynil herbicide at two levels (0 and 2 L ha-1) (I0 and I2), and the control (use of distilled water instead of herbicide). U-46 Combi Fluid and Duplosan Super herbicide treatments were applied at the end of September. Then, Ioxynil was applied 10 days after the first spraying. Finally, 15 days later, the effect of the treatments on the biomass characteristic of the dandelion shoots and the visual quality of turfgrass were recorded. After 50 days, the last spraying, the percentage of regrowth, herbicide control efficiency, and the biomass of turfgrass shoot were measured during the experiment. Variance analysis of data was done using SAS 9.1 statistical program and the comparison of means was conducted using LSD test (P≤0.05). Results and Discussion The results showed the lowest fresh and dry weight of dandelion and the highest efficiency of herbicide were found in treatments U2 + I2 and D2.5+ I2. However, these treatments had not significantly different from D2+I2 and U1.5+I2 treatments. The lowest percentage of regrowth was obtained in D2 + I2. The highest fresh weight of turfgrass was found in the control which had no significant difference with D2 + I2 and U1.5 + I2. Moreover, total chlorophyll in turfgrass leaves was improved by removing weeds. The amount of chlorophyll a, b, and total was higher in the U1.5 treatment than in other treatments. Therefore, improving the greenness of turf could be due to more light being provided to turf leaves as a result of dandelion leaf removal or positive physiological effects of 2,4-D or MCPA. There were no differences among treatments for total chlorophyll, carotenoid, visual quality, dry weight of turfgrass, and dandelion control percentage. Therefore, D2 + I2 and U1.5 + I2 can be recommended, due to the higher fresh turf weight, the good control of dandelion, and the low rate of regrowth of weed. Conclusion Application of Duplosan Super and then Ioxynil, both with a concentration of 2.0 L ha-1 and/or U-46 Combi Fluid with a concentration of 1.5 L ha-1 and then Ioxynil with a concentration of 2.0 L ha-1 treatments are recommended due to the high weight of turfgrass, the reasonable control of dandelions, and their reduction of regrowth. In addition, leaf chlorophyll of Kentucky bluegrass treated with of U-46 Combi Fluid with a concentration of 1.5 L ha-1 was higher than in other treatments. It also had a higher turfgrass fresh weight than the 2.0 L ha-1 of U-46 Combi Fluid treatment. Duplosan Super (2.5 L ha-1) and then Ioxynil (2.0 L ha-1) treatment led to a decrease in turfgrass fresh weight compared to the same treatment without Ioxynil. In conclusion, Ioxynil concentrations at high levels did not cause visible damage, but had adverse effects on turfgrass growth, suggesting that a lower dose should be studied.

Response of rice and weeds to seed priming under different weed management in direct-seeded

Ali Asghar Sobhani; Faezeh Zaefarian; Mohammad Kaveh; Arastaoo Abbassian

Volume 45, Issue 3 , December 2022, , Pages 421-434

https://doi.org/10.22055/ppd.2022.40389.2024

Abstract

Backgrounds and ObjectivesDirect seeding is being developed in many Asian countries as a new technology that farmers are tending to use this technology in current years considering ... Read More Backgrounds and ObjectivesDirect seeding is being developed in many Asian countries as a new technology that farmers are tending to use this technology in current years considering that it has appropriate economic efficiency, faster and easier cultivation, less labor force, more mechanization and shorter growth period than transplanting cultivation and due to discontinuous irrigation, less methane emission. But what makes it mainly obstacle are weeds.The use of seed priming can be one of methods that it can compensate the paucities of direct seeding and get promote seed quality. Seed priming also can active the initial germination mechanisms before planting and many benefits were mentioned for this treatment that the most significant of them is increasing the percentage and rate of germination. Indeed these plants expand their root system in shorter period of time compared untreated seeds. They are also reached to autotroph stage earlier by absorbing more water, nutrients and producing photosynthetic part. Materials and MethodsThe field experiment was conducted in Neka in 2018. The experiment was performed as a factorial in randomized complete block design in three replications. Experimental treatments include seed priming in four levels 1- no priming, 2- hydropriming (priming with water), 3- priming with humic substances (10 g per 1.5 liters of water) 4- priming with auxin hormone (1.5 cc in 1.5 liters of water) and also, weed management at five levels 1- no weeding, 2- council active herbicide (15 g per 20 liters of water), 3- twice weeding (one month after planting + before the earing stage), 4- council active herbicide (15 g per 20 liters of water applied about one month after planting) + weeding (1.5 months after planting) and 5- complete weeding (weeding of all weeds during the growing season). ResultsBased on the results, by applying seed priming with humic acid, the maximum plant height, ear length and number of plants m-2 were obtained and complete weeding caused the maximum plant height, fertile tiller, total tiller and ear length. Also, seed priming with humic acid along with complete weeding caused the highest filled grain number (79.67 number) and total grain number (90 number), 1000-grain weight (23.47 g), grain yield (2327 kg ha-1), biological yield (11220 kg ha-1). Based on total weed density and biomass, in all three stages of sampling, the lowest amount of weed biomass and density was obtained with application of humic acid priming along with council active herbicide + weeding, which was not significantly different from application of humic acid priming and twice weeding and application of auxin with council active herbicide + weeding and twice weeding. Overall, the findings of this study indicate the effect of priming of rice seeds especially with humic acid and auxin along with council active herbicide + weeding and twice weeding, on reducing the weeds density and biomass as well as increasing the yield and yield components of rice in direct cultivation. DiscussionAccording to results which were obtained this research and evaluation of yield and yield components are identified that application of herbicide cannot control the weed solitary. This research was showed that application of council active herbicide + weeding and twice weeding cause to reduce the weeds density and biomass as well as increasing the yield and yield components of rice in direct cultivation and also own to elimination of competing species, they improve the crop growth. Therefore, mechanical weeding, which is a non-chemical method of weed management, should be considered as a necessary part of sustainable agriculture.

Rapid test for Detecting Haloxyfop-R methyl Ester Resistance in Winter Wild Oat (Avena ludoviciana durieu)

Saeid Hassanpour-bourkheili; Javid Gherekhloo; Behnam Kamkar; Seyed Sanaz Ramezanpour

Volume 45, Issue 2 , September 2022, , Pages 267-276

https://doi.org/10.22055/ppd.2021.33123.1887

Abstract

IntroductionDetection of resistance to an herbicide in a putatively resistant accession requires a series of experiments which are capable of illustrating the response of the accession ... Read More IntroductionDetection of resistance to an herbicide in a putatively resistant accession requires a series of experiments which are capable of illustrating the response of the accession to various herbicide doses. Whole plant bioassay in pots usually takes approx. 2 months to obtain the results, thus, rapid tests were developed to accelerate the process. Although determination of discriminating concentration as well as conduction of rapid test for some ACCase inhibitors has been performed by various researchers, no reports are available in this regard for haloxyfop-R methyl ester herbicide in winter wild oat. Thus, the following study was conducted with the objective of rapid detection of resistance to the mentioned herbicide in this weed using the rapid test. Materials and MethodsThe experiment was conducted using the seeds of 7 putatively resistant winter wild oat accessions and a susceptible biotype gathered from canola farms of Kalaleh Township located in Golestan province in 2015. Rapid test in petri dishes was conducted as a completely randomized design with three replications, with each petri dish as one replicate. To determine the discriminating concentration, various concentrations of haloxyfop-R methyl ester was applied on the susceptible accession and then, all putative accessions were screened using this concentration. The biotypes of the studied weed were exposed to various doses of the herbicide in the petri dish bioassay to determine the resistance factor. Also, a completely randomized design experiment with three replications was conducted for screening of putative accessions in the greenhouse. Accessions which maintained their survival and dry weight respectively 50 and 80 percent compared to the unsprayed control were selected. A whole plant dose-response bioassay was also done separately for each biotype. Results and DiscussionDiscriminating concentration of haloxyfop-R methyl ester for winter wild oat was obtained 0.106 mg ai. L-1. According to the results, 5 out of 7 accessions were detected as resistant and underwent the concentration- response assay in petri dishes. Resistant factors of the biotypes in the rapid test ranged from 2783.054 to 3421.414. However, no significant difference was observed among the biotypes. According to the results of the greenhouse, 5 accessions were detected as resistant with resistance factors of 14.19 to 18.54, with no significant difference among the biotypes. There was a positive and significant correlation between the results obtained from the rapid test with the greenhouse assay, which indicates the validity of the Petri dish assay. ConclusionThe results of the rapid test are in accordance with those of the whole plant assay in pots. Therefore, putative winter wild oat accessions collected from the region may be screened using the obtained concentration of haloxyfop-R methyl ester (0.106 mg ai. L-1) and resistant biotypes may be detected more rapidly compared to greenhouse assays. Due to the swift development of herbicide resistance issue, rapid detection of resistance is essential. Thus, using methods such as rapid test may be very feasible.

Cogongrass (Imperata cylindrica L. Beauv) Management in Sugarcane Fields of Subtropical Iran

Farkhondeh Eskandari; Batool Keramat; Yousef Filizadeh; Amir Aynehband

Volume 45, Issue 1 , May 2022, , Pages 123-132

https://doi.org/10.22055/ppd.2020.33905.1919

Abstract

IntroductionAmong all weeds, cogongrass (Imperata cylindrica L. Beauv) has been identified as a problematic weed in the sugarcane (Saccharum officinarum L.) fields of Iran for over ... Read More IntroductionAmong all weeds, cogongrass (Imperata cylindrica L. Beauv) has been identified as a problematic weed in the sugarcane (Saccharum officinarum L.) fields of Iran for over 20 years since 1996. Failure to control of cogongrass regrowth during spring develops it rapidly and, in turn, reduces the sugarcane yield in subtropical Iran. In effect, the identification of weak points in cogongrass phenology and frequency is deemed to help decision makers adopt effective controlling strategies in optimum time. Storage of carbohydrate reserves by plants is, in turn, the best mechanism for optimizing the timing of management strategies when reserves are at the lowest levels in storage organs. Glyphosate has been also widely used in Iran to control of weeds in the sugarcane fields. Currently, despite double spraying, the spring control of cogongrass is not satisfactory in the sugarcane fields in subtropical Iran. Materials and MethodsTwo studies were carried out in Salman Farsi Agro-Industrial Company in about 40 km south-west of the center of Khuzestan Province, Ahvaz, Iran, in 2017. In the first experiment, monthly (February–November) total nonstructural carbohydrate allocation patterns of cogongrass were evaluated to determine carbohydrate low points in the seasonal phenological cycle. To that end, glyphosate (00, 0.92, 1.84, 2.76 and 3.68 L a.i ha-1) was applied in April and June, 2017, in a 10×2 factorial design under randomized complete block designs with four replications. Data were analyzed using standard ANOVA procedures with the subsequent use of Least Significant Difference test (Little and Hills 1978( to separate means. Results and DiscussionThe occurrence of carbohydrate low points (CLPs) (88.69±13.15 mg g-1) was considered from May to August, CLP was found to have two important points with the potential control of cogongrass reported. The first and second points were in May (579 GDD) and August (2683GDD), respectively. The suppression of cogongrass (58-100%) was achieved with the three highest rates (1.84, 2.76 and 3.68 L a.i ha-1) in both application times, although substantial regrowth occurred in all plots by 5 months after the first treatment. Double spraying with a 60-day interval did not result in the effective control of such a troublesome weed in the sugarcane fields. Applying glyphosate two times in the spring and mid-summer (the end of CLP, 2683 GDD) was determined effective for the long-term control (>6 months) of cogongrass. The results suggest that glyphosate 1.84 L a.i ha-1 should be performed on cogongrass in the spring for improved control. ConclusionWe concluded that frequent spring spraying may be excluded to control of cogongrass in the sugarcane fields and only spraying should be made on twice the growth seasons. The first use of glyphosate in its minimum optimum dose (1.84 L a.i ha-1) is made on early spring. The second is sprayed in its maximum optimum dose (3.68 L a.i ha-1) at the midsummer, once the single-sprayed cogongrass gets appropriate leaf surface for transferring the herbicide.

Effect of the Vertical and Non-Vertical Spray of Flat Fan Nozzle Types on the Control Efficacy of Winter Wild Oat (Avena sterilis subsp. ludoviciana Durieu.) by Haloxyfop-R-methyl

Akbar Aliverdi; Samira Karami

Volume 44, Issue 3 , December 2021, , Pages 331-344

https://doi.org/10.22055/ppd.2020.32527.1875

Abstract

AbstractBackground and ObjectivesSince the leaves of a grass species are perpendicularly oriented to the ground, spraying an ACCase inhibitor with a conventional hydraulic nozzle can ... Read More AbstractBackground and ObjectivesSince the leaves of a grass species are perpendicularly oriented to the ground, spraying an ACCase inhibitor with a conventional hydraulic nozzle can not cause an adequate control. In such a situation, it is well established that a large endo-drift of the spray droplets can be occurred. Recently, a new spray technique, angled spray, has been introduced to maximize the deposition of spray droplets on a vertical target surface (i.e., grassy species). This technique is simple, inexpensive, and available to farmers. Therefore, it can be noteworthy to them. This reserech aimed to study the effect of many angled sprays by three flat fan nozzle types on the efficacy of haloxyfop-R-methyl against winter wild oat.Materials and MethodsThis study was conducted as dose-response bioassay at the research greenhouse of Bu-Ali Sina University in 2019. Haloxyfop-R-methyl at seven doses (0, 5.06, 10.12, 20.25, 40.5, 60.75, and 81 ml a.i. ha-1) were sprayed at 300 kPa spray pressure using three flat fan nozzle types having different atomization quality (standard (Fine: 144–235 µm), anti-drift (Medium: 236–340 µm), and air induction (Extremely Coarse: 503–665 µm)) in seven angled sprays (vertical spray and non-vertical sprays with 10, 20, 30, 40, 50, and 60° forward) on winter wild oat at the three-leaf stage. The haloxyfop-R-methyl dose required to give a 50% reduction in dry weight of winter wild oat (ED50) was detected. ResultsThe ED50 values were significantly affected by the nozzle type and the spray angle. With a vertical spray, the ED50 values of 32.51, 44.05, and 53.98 ml a.i. ha-1 was obtained from the flat fan nozzles of standard, anti-drift, and air induction, respectively. The best efficacy of haloxyfop-R-methyl was obtained using a 30° forward angled spray by standard flat fan nozzle (ED50 = 15.10 ml a.i. ha-1), a 40° forward angled spray by anti-drift flat fan nozzle (ED50 = 17.13 ml a.i. ha-1), and a 50° forward angled spray by air induction flat fan nozzle (ED50 = 17.61 ml a.i. ha-1). DiscussionFrom this experiment, the following points were obtained: 1) with a vertical spray, there is a negative correlation between the herbicide efficacy and the spray droplet size; 2) with a non-vertical spray, there is a neutral correlation between the herbicide efficacy and the spray droplet size; 3) when the droplets produced by a nozzle is larger, the more non-vertical spray is required to obtain maximoum herbicide efficacy.

The Effects of Additives on the Efficacy of Herbicides of Othello, Topik+ Granstar, Total and Apirus in Controlling Wild Oat and Charlock Mustard as Dominant Weeds of Wheat

Abbas Rahpeyma; Mehdi Madandoust

Volume 44, Issue 4 , December 2021, , Pages 503-514

https://doi.org/10.22055/ppd.2020.33688.1913

Abstract

AbstractIntroductionAdding an adjuvant facilitates the uptake of herbicides through the aerial parts of plants and reduces the selective state of the herbicide. If the amount of adjuvants ... Read More AbstractIntroductionAdding an adjuvant facilitates the uptake of herbicides through the aerial parts of plants and reduces the selective state of the herbicide. If the amount of adjuvants is more than the amount needed to moisturize the surface of the plants, the penetration of herbicides will increase. The experiment reported here was conducted to determine the best additives on increasing the effectiveness of herbicides in controlling wheat weeds. Materials and MethodsThe experiment was conducted in a randomized complete block design with three replications in a farm in Fasa (28° 56' N, 53°38′E) during 2017-2018. The factors consisted of herbicides in four levels of Mesosulfuron+ Iodosulfuron+ Diflufenican (Othello), Clodinafop Propargyl (Topik)+ Tribenuron–Methyl (Granstar), Sulfosulfuron+ Metsulfuron Methyl (Total) and Sulfosulfuron (Apirus) in recommended doses and type of additives in 4 levels, Ammonium Sulfate 2%, soybean oil 1.25%, cleaner liquid as surfactant Anionic 0.5% and without additive as control. Wheat seeds of Chamran cultivar with vigour of 98% at rate of 150 kg.ha-1 were planted in rows of 10 cm. The dimensions of each experimental plot were 2´4 m. Herbicide application time was also in the wheat tillering and 2-4 leaf weeding stages. The experimental sprayer was used with a manual pump, having a nozzle with a spray angle of 30 degrees, a constant pressure of 50 psi and a spray height of 20 inches (50 cm) calibrated for spraying. Characteristics such as dry weight of narrow weeds included wild oat (dominant weed) along with canary grass and Ryegrass, broad-leaf weeds including charlock mustard (dominant weed) along with fumitories were measured. Number of spikes per square meter, number of seeds per spike, 1000 grain weight, biological yield, grain yield and wheat harvest index were measured too. Results and DiscussionThe results showed that among the additives used, 2% Ammonium Sulfate had the greatest effect on reducing the dry weight of weeds, narrow-leaf (34.05%) and broad-leaf (31.57%) weeds. The herbicides Othello, Topik+ Granstar and Total had performed well on wheat grain yield, but did not result in significant differences. The combination of additives with herbicides compared to no adjuvant control increased grain yield (on average, 607.73 kg.ha-1). Finally, Othello herbicide was identified as the best treatment for this test due to its consumption of 2% Ammonium Sulfate additive. The effect of herbicides application of Othello, Topik+ Granstar and Total on grain yield can be due to their effect on decrease of weed dry weight. The results indicate that Ammonium Sulfate 2% increased the uptake of herbicides ,accordingly it increases the effectiveness of herbicides in weed control and grain yield increase. ConclusionCombining each of the adjuvants with herbicides increased the grain yield of wheat. Among the additives, Ammonium Sulfate was the most effective. 2% Ammonium Sulfate with an average yield of 6203 kg.ha‑1 showed the highest effect. The results of the means revealed that the herbicides Apirus, Othello and Total had the greatest effect on increasing wheat grain.

Integrated Mechanical Weeding and Herbicide Application in Weed Management of Sugarcane (Saccharum officinarum L.)

Yousef Rezaie; Elham Elahifard; Seyed Ataollah Siadat; Sasan Abdolahi Lorestani

Volume 44, Issue 2 , August 2021, , Pages 171-182

https://doi.org/10.22055/ppd.2020.30228.1788

Abstract

AbstractIntroductionWeeds are among the most important factors reducing sugarcane yield in Khuzestan province. Sugarcane has a vegetative stage susceptible to weed competition, which ... Read More AbstractIntroductionWeeds are among the most important factors reducing sugarcane yield in Khuzestan province. Sugarcane has a vegetative stage susceptible to weed competition, which is about 3 to 6 weeks from the time of planting in a warm and humid season. Therefore, the control of weeds in the early part of the growing season before the canopy closure of sugarcane and covering more than half the rows of planting is very critical. In order to investigate the effect of combination of mechanized weeding and application of three herbicides including indaziflam, 2,4-D + MCPA + metribuzin, on weed control and sugarcane yield, a field experiment was conducted in Ratoon2 field in 2017-2018 growing season in Dehkhoda Sugarcane Plantation and Industry Company, Khuzestan, Iran. Materials and MethodsThe experimental design was split plot based on randomized complete block design with three replications. Mechanical weeding at three levels (sweep cultivator, rotavator, and no cultivation) was considered as the main plots. Herbicide application was considered as sub plot at three levels [indaziflam (50 ml ai ha-1), 2,4-D + MCPA + metribuzin (675 ml ai ha-1 + 1050 g ai ha-1) and no herbicide application (as weedy control)]. A weed- free check was included for comparison. Herbicide applications were made using backpack sprayer with TeeJet 11004 flat fan nozzle calibrated to deliver 250 L ha-1 at pressure of 2.5 atm. Sugarcane cultivar was CP-614. Weed sampling was carried out 60 days after treatment. Single stem weight, cane yield, final sugar yield, brix, pol, sugar purity and recoverable sugar were measured at the end of growing season and after sugarcane harvest. Results and DiscussionThe results showed that mechanical weeding treatments lead into reduced weed dry weight. As a result, weed control was more effective in rotavator treatment than cultivator. Maximum reduction weed dry weight (52.47%) was observed in integrated rotavator and indaziflam treatment. The results of the quantitative traits of sugarcane showed that using mechanized weeding and herbicide application, caused an increase in weight of single stem and yield of cane compared to the control. The greatest single stem weight was observed in cultivator treatment plus 2,4-D + MCPA + metribuzin (1.65 Kg m-2), rotavator + 2,4-D + MCPA + metribuzin (1.63 Kg m-2) and indaziflam (1.61 Kg m-2). The final sugar yield (9.79 t ha-1) in indaziflam treatment was greater than other treatments (except weed -free treatment). However, the measured values of Brix, pol, sugar purity and recoverable sugar did not differ significantly among treatments. Results showed that the use of mechanized weeding combined with herbicide applications would have an effective role in improving sugarcane yield and inhibition of sugarcane weeds. ConclusionThe use of herbicides at the beginning of the sugarcane growing season led to more effective weed control; As a result, competition between sugarcane and weeds in access to food resources decreased, which led to the growth and development of sugarcane. However, the indaziflam did better than 2,4-D + MCPA + metribuzin due to its slight superiority in single-stem weight and cane yield. In general, it can be said that the use of mechanical weeding has an important role in controlling sugarcane weeds and the use of rotivator had a significant advantage over cultivator. According to the results of single stem weight, the use of combination weeding with herbicides will play an effective role in improving the weight of sugarcane.

Effect of Permissible Inhibitors from Mixing of Several Medicinal Plants on Weed Seed Bank to a Depth of 20 cm Soil

vahid Chamani; Elnaz Farajzadeh-Memari-Tabrizi

Volume 44, Issue 1 , June 2021, , Pages 115-128

https://doi.org/10.22055/ppd.2020.28826.1748

Abstract

AbstractBackground and ObjectivesWeed seed bank in the soil is an essential source of weeds that enables them to be present in the fields. The seed bank density in a crop may reach ... Read More AbstractBackground and ObjectivesWeed seed bank in the soil is an essential source of weeds that enables them to be present in the fields. The seed bank density in a crop may reach a million seeds per square meter. Depending on the crop operation, crop rotation, and herbicide selection, the weed seed bank differs according to the location and time. Due to the economic benefits and improved crop ability, plant remains have become an attractive and acceptable way in agriculture. Allelopathic plant remnants can have a beneficial effect on weed control. The allelopathy of these plants plays a vital role in controlling the seed bank of weed soils. Therefore, this study was conducted to investigate the effect of mixing different amounts of residues of three medicinal herbs on the potential of the weed seed bank in the Malekan region. Materials and MethodsThis study was carried out at Malakan Azad University labs in 2018. Treatments included mixing different amounts of residues (0, 50, 100, and 150 g / m2), and three medicinal plants were cumin, seaweed, and marjoram. Samples had taken from a depth of 0 to 20 cm in an ocher system (7 cm radius) to measure the soil's seed bank. Weeds were isolated, and their species were identified. Laboratory studies were conducted to determine the germination strength of these seeds. This part of the experiment was carried out with three replications in a completely randomized design. ResultsIn total, 53915 weed seeds were detected per square meter. The highest seeds in the soil belonging to weed carnivorous and lambspeed were 33254 and 12457 seed per square meter of soil, respectively. The seeds of these two weeds included 95.4% of the seed bank of soil weeds. In this study, the remnants of seaweed and marigold caused a significant decrease in germination characteristics and the growth of seedlings of these weeds. Remains of cumin have little effect on the traits studied. Seed germination and seedlings growth of these weeds decreased by 44.7% and 84.9%, respectively. Discussion By increasing the amount of application of the remains, a more significant reduction in germination and weed growth was achieved. The remnants of the two herbs had a similar effect on germination and seedling growth. Overall, this study showed that the remnants of medicinal plants could reduce the diversity and abundance of seed banks of soil weeds.

Weed Population and Nutrient Uptake by Wheat as Influenced by Different Tillage Practices and Weed Management Options in Ahvaz

Rahim Nor Aftab; Ali Monsefi; Afrasiyab Rahnama Ghahfarokhi; Amir Aynehband

Volume 44, Issue 1 , June 2021, , Pages 143-156

https://doi.org/10.22055/ppd.2021.34868.1938

Abstract

AbstractBackground and ObjectivesWeeds often pose severe constraints in the potential yield of wheat, if not controlled at a critical period of the first 30 days after sowing. Several ... Read More AbstractBackground and ObjectivesWeeds often pose severe constraints in the potential yield of wheat, if not controlled at a critical period of the first 30 days after sowing. Several methods are developed to control weeds, viz. cultural, mechanical, and chemical have their own merits and demerits. Tillage is an age-old practice to control weeds. Tillage influences weed infestation, and thus interactions between tillage and weed control practices are commonly observed in crop production. Good tillage delays the emergence of weeds and provides a more favorable environment for early crop establishment. So, the competition for nutrients will be less. Materials and MethodsThis study was conducted to investigate the weed population and evaluate the nutrients uptake by wheat and weed in a split-plot design with three replications in the research farm of the Shahid Chamran University of Ahvaz in the year 2018-19. Tillage at three levels, including conventional tillage, minimum tillage, and zero tillage, as the main plot and weed control at six levels (uncontrolled, hand weeding, bromoxynil + MCPA herbicide, crop residue + Atlantis, Atlantis, and metribusin) as Post-emergence were considered in sub-plots applied on wheat of Mehregan cultivar. ResultsIn terms of the weed population, the highest weed population was observed in the zero tillage compared to conventional tillage and minimum tillage. In this regard, under uncontrolled treatment, the highest weed populations with an average of 16.3, 14.2, and 12.5 plants per square meter were observed at 30, 60, and 90 days after sowing, respectively. In the case of an interaction effect, it was found that in all three tillage systems, the highest amount of nutrients, including nitrogen, phosphorus, and potassium, absorbed by weeds was in the uncontrolled treatment. The reason was due to higher dry matter production and higher competition with wheat as it was incremental. DiscussionIn general, considering the higher weed population in the zero tillage as compared to the conventional tillage, it seems that weed control in the zero tillage and minimum tillage, at least in Khuzestan province, is preferable to prevent moisture content and soil structure. Nutrient depletion by weed is less in conservation tillage so that nutrient availability will be as much as plant requirements.

Effect of Green Manure under Different Conditions of Tillage on Weed Characteristics and Corn (Zea mays L.) Yield

Mohammad Sorkheh; Faezeh Zaefarian; Mohammad hossain Gharineh

Volume 43, Issue 2 , September 2020, , Pages 281-294

https://doi.org/10.22055/ppd.2019.27385.1665

Abstract

Abstract Background and ObjectivesHigh degree of evaporation from soil surface (due to high temperature of environment and low relative humidity), poor soil organic content and ... Read More Abstract Background and ObjectivesHigh degree of evaporation from soil surface (due to high temperature of environment and low relative humidity), poor soil organic content and instability of soil structure are considered indicators of arid regions of Iran. It seems that in a regional management, conservation of plant residues with irrigation operations in the absence of a negative effect on yield can be used as a way to improve the above-mentioned conditions. The management of plant residues has been interesting to researchers in recent decades due to its various effects on the physical, chemical and biological properties of soil. On the other hand, protective tillage can help to maintain more soil moisture, reduce erosion and less use of agricultural machinery, thereby achieving sustainable agriculture and reducing costs. This research was conducted to investigate the effect of application of wheat residues and green manure along with different tillage systems on corn. Materials and MethodsThis experiment was conducted in Shush, Khuzestan Province in 2015-2016, as strip-plot in randomized complete block design with three replications. The main treatment consisted of conventional and minimum tillage methods. The sub-plot treatment applied mulches such as wheat residue, two types of green manure (mung bean (Vigna radiata L.) and cowpea (Vigna unguiculata L.)) and control (no fertilizer application). The characteristics in this research included grain yield, biological yield, number of rows in corn, number of kernels per row, 100 grains weight, and weed growth indices (density, variety and dry weight in two stages: 4 to 6 leaf and maturity of corn). ResultsMaximum grain yield of corn was obtained in wheat residue (10399.27 kg ha-1). Also, there was no significant difference in plants treated with green manure of cowpea (10013.49 kg ha-1). The lowest economic yield was seen in control (7382 kg ha-1). Similar to grain yield, the highest biological yield of corn occurred with application of minimum tillage (16139.14 kg ha-1), wheat residue (17170.89) and cowpea green manure (16790.37 kg ha-1). Besides, the best treatment to reduce the number, variety and dry weight of weeds, was achieved with green manure in minimum tillage. Based on the results, the dominant weed of the field in conventional tillage in 4 to 6 leaf stage was physalis (Physalis alkekengi) while it was common purslane (Portulaca oleracea) in the minimum tillage. In maturation of corn, both in conventional tillage and minimum tillage, the dominant weed was physalis, which had the highest dry weight of weeds in every stage. DiscussionBased on the results of this research, application of wheat residues and cowpea green manure combined with minimum tillage can be a suitable way to increase corn yield and reduce weed diversity and biomass in sustainable agriculture.

The Effect of Thermal Shock, Burial Depth and Seed Position on Germination of eeds of Heteromorphism Hedge Parsley (Torilis arvenis)

Rezvan Payamani; Iraj Nosratti; Masoomeh Amerian

Volume 43, Issue 1 , June 2020, , Pages 1-12

https://doi.org/10.22055/ppd.2019.26379.1621

Abstract

Abstract Background and Objectives Weeds are one of the most important factors that affect and reduce the yield of crops. Hedge parsley produces two shapes of seeds, fluffy and ... Read More Abstract Background and Objectives Weeds are one of the most important factors that affect and reduce the yield of crops. Hedge parsley produces two shapes of seeds, fluffy and non-fluffy, of their germination behavior little information is available. The aim of this study was to investigate the effect of seed position, burial depth, thermal shock and seed polymorphism on germination percentage of hedge parsley. Materials and Methods The experiments were conducted based on factorial experiment in completely randomized design (CRD) with three replications at campus of agriculture and natural resources during years 2016-2017. In the first experiment, the factors included seed position (high, middle and low plants), temperature (20 and 25 C°) and seed shape (fluffy and non-fluffy). In the second experiment, the factors were thermal shock (100, 150 and 200 C°), burial depth (0, 2 and 4 cm) and seed shape (fluffy and non-fluffy). Results In the first experiment, with increasing temperature from 20 to 25 C° germination percentage decreased and at 20 C° the highest germination percentage (73.33%) was observed. Seed shape also affected seed germination percentages. In the second experiment, the burial depth had a positive effect on seed germination and with increasing burial depth, seed germination percentage increased. Interaction of thermal shock and burial depth showed that increasing burial depth and temperature increased the percentage of germination (57.14%). In both shapes of seeds, germination percentage increased with increasing burial depth and the highest germination percentage was observed in the maximum burial depth (4 cm). Discussion The results of this study showed that this weed is capable of germination in a wide range of environmental conditions. Germination percentage of hedge parsley increased with increasing burial depth. The optimum temperature for seed germination of hedge parsley is 20 C°. Seed shape was affected on seed germination percentage of hedge parsley.

Evaluating the Effect of Pendimethalin Herbicide Residue on Wheat and Barely

Taj Mohammad Khajavi; Zeinab Avarseji; Ebrahim Gholam Alipour Alamdari; Abbas Biabani

Volume 42, Issue 4 , December 2019, , Pages 483-494

https://doi.org/10.22055/ppd.2019.25477.1589

Abstract

Abstract Background and Objectives Nowadays, herbicides are crucial for modern agricultural systems. Yet, improper application of herbicides will have dangerous consequences. ... Read More Abstract Background and Objectives Nowadays, herbicides are crucial for modern agricultural systems. Yet, improper application of herbicides will have dangerous consequences. For example, there will be crop damage due to long lasting herbicide residue or herbicide drift on neighbor crops if applied on non-target species. The purpose of this experiment was to determine the sensitivity of wheat and barley to pendimethalin residue by using bioassay. Materials and Methods In order to evaluate soil residue of pendimethalin, experiments with completely randomized designs were carried out in the greenhouse at Faculty of Agricluture and Natural Resources of Gonbad Kavous University. In this experiments, different doses of pendimethalin (0, 1, 5, 10, 15, 20, 30, 40, 50, 75 and 100 % of recommended dose) were applied on wheat and barley in order to measure the dry weight of root and shoot of crops. The concentration of herbicides was made by dilution of stock solvent. Three/four-parameter log-logistic curves were used for fitness of the data. Results Results indicated that almost all data followed the three-parameter logarithm logistic curve. Results of separate fitness of data showed that the residue of pendimethalin always caused reduction of dry weight of the evaluated crops. Fifty percent reduction of shoot dry weight of wheat and barley was obtained from 400.5 and 623.05 g.a.i.ha-1 of pendimethalin and the ED50 values of root dry weight of wheat and barley were 65.88 and 269.66 g.a.i.ha-1 of pendimethalin, respectively. Discussion Generally, the results of simultaneously fitted data shows that wheat is always more sensitive to pendimethalin rather than barley. Based on results, even the very little portion of herbicides can cause damage to crops, thus, considering the sensitive crop in rotation is so important since this residue can stay active even in two-season crops and make crop injuries. The selection between 3 and 4 Logarithm logistic model was based on: 1. Lack of fit test significance 2. Significance of estimated parameters, especially the parameters and the way of distribution of data around the curve (graphical observation).

Chemical Control of Cynanchum acutum in Sugarcane Plant Fields

Iman Ahmadi; Mohammad hossain Gharineh

Volume 42, Issue 1 , April 2019, , Pages 103-114

https://doi.org/10.22055/ppd.2019.24376.1545

Abstract

Abstract Background and Objectives Weeds are the most important factors in sugarcane yield loss. Successful weed control is essential for economical sugarcane production. Weeds ... Read More Abstract Background and Objectives Weeds are the most important factors in sugarcane yield loss. Successful weed control is essential for economical sugarcane production. Weeds can reduce suercane yields by competing for moisture, nutrients, and light during the growing season. Weed control is most critical early in the season prior to sugarcane canopy closure over the middle rows middles. Herbicides can be useful and economical tools in sugarcane production. Indaziflam is an alkylazine herbicide that is labeled for use in turf, for perennial crops and for nonagricultural situations for preemergent control of grasses and broad leaf weeds. The objective of this research was evaluation of the efficacy of indaziflam on control of Cynanchum acutum in sugarcane fields in Khouzestan, Iran. Materials and Methods The experiment was conducted in 2015 growing season in a sugarcane field Shoaeibiyeh, Shoushtar, Khouzestan, Iran. The trial was randomized in complete block design with four replications. Variety and type of culture were Cp69-102 and plant, respectively. Treatments were 1-indaziflam (75 g ai ha-1, as preemergence); 2-indaziflam (50 g ai ha-1 as preemergence); 3- Trifloxysulfuron sodium + ametryn (1875 g ai ha-1,as postemergence); 4-2,4-D+MCPA (1687.5 g ai ha-1); 5-glyphosate + Ammonium sulfate 6- weeding and 7- weed infested. The herbicides were applied with backpack sprayer equipped with flooding and T-jet nozzles calibrated to deliver 300 L ha-1. Every two weeks, dry weight and density reduction percentage of Cynanchum acutum were measured and 90 days after herbicide applying, stem length, stem weight, the middle internode diameter and length of sugarcane and also purity, pol and recoverable sugar of sugarcane were determined. Statistical calculations were accomplished through the SAS 9.2 software and graphs were drawn by the Excel software. Results However, indaziflam efficacy was reduced over time. Other herbicides such as indaziflam as50 g ai ha-1 and trifloxysulfuron sodium + ametryn indicated a good effect in Cynanchum acutum control compared with 24-D + MCPA and glyphosate + Ammonium sulfate. Single stem weight (0.72 kg), the middle internode diameter (1.85 cm), number of internode (18. 2 cm) and cane yield (117.90 t ha-1) were the greatest in indaziflam (75 g ai ha-1). The greatest brix (21.48%), invert sugar (0.533%), recoverable sugar (11.26%) and the lowest fiber content (12.61 t ha-1) were obtained in indaziflam treat (75 g ai ha-1). Discussion The present research indicatedindaziflam could control Cynanchum acutum in sugarcane field although indaziflam efficacy was reduced over time. However, there were no adverse effects of indaziflam rates on sugarcane observed; therefore, this herbicide could be used in sugarcane fields. Since highly intensive use of herbicides in fields causes to herbicide resistance, herbicides with different mechanisms of action should be registered for weed control of sugarcane. Because of low volume of indaziflam as compared to current herbicide of sugarcane, this is a good candidate for application in sugarcane fields in rotation or mixture with other recommended herbicides.

Studying the Effect of Mesosulfuron Methyl + iodosulfuron Methyl on Chlorophyll Fluorescence Parameters of Phalaris Minor

Z. Avarseji; E. Mohammadvand

Volume 41, Issue 3 , December 2018, , Pages 63-72

https://doi.org/10.22055/ppd.2018.21851.1468

Abstract

Abstract Background and Objectives Measuring of chlorophyll fluorescence is a nondestructive and sensitive way to give important information about photosynthesis apparatus. Fluorescence ... Read More Abstract Background and Objectives Measuring of chlorophyll fluorescence is a nondestructive and sensitive way to give important information about photosynthesis apparatus. Fluorescence spectrum is different from the absorbed one by chlorophyll and it has higher wave length so the fluorescence yield could be measured by exposing a leaf with a defined wave length of light and then quantifying the higher reflected wave. The purpose of this experiment was to make comparison among chlorophyll fluorescence important parameters for early prediction of destructive effects of mesosulfuron methyl + iodosulfuron methyl before revealing the symptoms of Phalaris minor. Materials and Methods A greenhouse experiment with five replications and six treatment based on completely randomized design was conducted to evaluate the chlorophyll fluorescence parameters of Phalaris minor sprayed by mesosulfuron methyl + iodosulfuron methyl up to seven days after spraying.Herbicide doses were 18, 12, 8, 5.3 and 3.5 g a. i./ha with an untreated treatment as control. Herbicide was applied at three leaf stage of Phalaris minor with MATABI elegance plus sprayer equipped by tee-jet 8001 nozzle at 300 kpa pressure. Fluorescence measurements were conducted by Handy PEA fluorimeter that flashes a wave length of 650 nm at 300 μ mol/m2.s intensity during 10 seconds on dark adapted leaf one day after spraying at 10 a.m. every day until seven days after spraying. Results The results indicated that Fv/Fm and Area parameters showed slow response to mesosulfuron methyl + iodosulfuron methyl application whereas Fvj and PI showed a fast reaction. Approximately from the first day after spraying the two mentioned parameters drastic reduction happened which was more intense but with bigger standard errors in PI compared to Fvj. with an increase in mesosulfuron methyl + iodosulfuron methyl dose both PI and Fvj parameters were decreased. Discussion It could be concluded that these two parameters show special sensitivity to the mesosulfuron methyl + iodosulfuron methyl application and before the symptoms of the herbicide appears, they give a picture of physiological destructive effects of the herbicide.Whereas the Fvj parameters during all seven days after spraying shows a steady reduction with low standard errors, PI index shows reduction with higher standard errors which make the Fvj parameters more reliable. The two Fv/Fm and Area which were repeatedly reported as a sensitive factor to the stresses at this experiment were not appropriate indices. The common dose response methods of herbicide can be replaced by chlorophyll fluorescence measurements and it can offer fast, accurate, and an important information about herbicide efficiency very fast and accurate.

Identification of resistant Avena ludoviciana Dur Accessions to ACCase Inhibitor Herbicides in Gonbad-E Kavus Wheat Fields and Mapping Their Distribution

S. Tatari; J. Gherekhloo; A. Siahmarguee; H. Kazemi

Volume 41, Issue 2 , September 2018, , Pages 103-116

https://doi.org/10.22055/ppd.2017.21015.1439

Abstract

Abstract Background and Objectives Wheat is the most important crop in Iran and every year about 6.5 million ha of arable lands in the country is cultivated by this strategic crop. ... Read More Abstract Background and Objectives Wheat is the most important crop in Iran and every year about 6.5 million ha of arable lands in the country is cultivated by this strategic crop. Weeds cause 23 to 30% reduction in yield of wheat annually. Winter wild oat is the most serious grass weed of wheat fields of Iran. Chemical method is the common way to weed control in wheat fields. ACCase inhibitors such as clodinafop-propargyl, diclofop-methyl and Fenoxaprop-P ethyl + Mefen pair di ethyl are widely used for control of grasses in this regard. Continuous application of herbicides with the same mode of action has resulted in developing herbicide resistant biotypes of weeds such as Avena ludoviciana. The objectives of the current study were: 1) to screen the collected accession of A. ludoviciana suspected to resistance to FOP herbicides, 2) to determine the resistance factor of resistant biotypes and 3) mapping distribution of resistant biotypes. Materials and Methods In order to survey Avena ludoviciana resistance to clodinafop-propargy, diclofop-methyl and Fenoxaprop-P ethyl+ Mefen pair di ethyl herbicides in wheat fields of Gonbad-e Kavus, several experiments were conducted in 2014 at Gorgan University of Agricultural Sciences and Natural Resources. (115 populations). The seed bioassay in Petri dish and pot experiment was conducted to determine resistance to acetyl coenzyme Acaboxylase inhibitors (ACCase), respectively. The seed bioassay experiment consisted of screening the suspected populations with discriminating concentration and concentration-response bioassay for resistant populations. Results In 48, 27 and 21 populations of A. ludoviciana were resistant to clodinafop-propargyl, diclofop-methyl and Fenoxaprop-P ethyl + Mefen pair di ethyl herbicides. Resistance accessions indicated varying degrees of resistance to tested herbicides. Based on EC50, the lowest and highest resistance to Clodinafop-propargyl herbicide was shown in Accessions of 74 and 6 with resistance factors of 1.99 and 31.42, respectively. Also for Diclofop- methyl herbicide, EC50 values from 2.88 for accession of 103 (with 1.34 resistanc factor) to 16.02 for accession of 91 (with 7.45 resistance factor) were different. In addition, EC50 estimatedfor Fenoxaprop-P ethyl + Mefen pair di ethyl herbicide was different from 0.124 to 0.86 for 20 and 6 accessions, respectively. Checking the distribution map of resistance accessions showed these accessions had uniform distribution in this city. Discussion Based on these observations, the existence of cross-resistance to herbicides was proved in some of the collected accessions. The results of this study can be used to correct programs designed to manage weeds herbicide resistance and prevent of the development of the plants in other areas.

Evaluating the Wheat (Triticum aestivum) Yield Loss Caused by Wild Oat (Avena fatua) Interference at Nitrogen Different Levels

j. pourreza

Volume 40, Issue 3 , December 2017, , Pages 41-52

https://doi.org/10.22055/ppd.2017.18933.1372

Abstract

Abstract Background and Objectives Wild oat was described as a vigorously growing weed with a capability to attain greater height, and establish and develop extensive leaf area and ... Read More Abstract Background and Objectives Wild oat was described as a vigorously growing weed with a capability to attain greater height, and establish and develop extensive leaf area and horizontal branches when moisture and nutrients are not limiting. Fertilization is an important agronomic strategy used extensively to increase crop yield. Although, the effect of fertilizers is extensively investigated in wheat, there is little information to assess the effect of fertilizer application on wheat yield loss due to wild oat interference. The objective of this study was to investigate the wheat yield loss caused by wild oat interference at nitrogen different levels. Materials and methods In order to evaluate the wheat yield loss caused by wild oat interference at different nitrogen levels, a field experiment was conducted at a farm in Ramhormoz city (latitude 31.16°N, longitude 49.36°E and 151 m asl), south-west of Iran in 2011-2012. The experiment was designed as a randomized complete block with a split plot arrangement with nitrogen fertilizer (N0: unfertilized control, N1: the use of 150 N Kg ha-1 before wheat seeding and N2: the use of 50 N Kg ha-1 before wheat seeding + 100 N Kg ha-1 at late tillering stage of wheat) as the main plot and wild oat density (D0: weed- free control, D1: 25, D2: 50, D3: 75 and D4: 100 plants m-2) as the subplot with three replications. Results A hyperbolic function was used to describe yield loss-density relationship. Increasing wild oat density had asymptotic-type effect on wheat yield loss. Initial slope (i) of the rectangular hyperbola model was a significantly greater when nitrogen fertilizer was applied. Moreover, for the rectangular hyperbola model, there was significant effect of nitrogen application on estimated maximum wheat yield loss (A). Application of 150 N Kg ha‑1 (N treatment) \before crop seeding resulted in a greater competitive ability of wild oat than other treatments. Discussion The results of this study suggest that the application of nitrogen fertilizer increases wild oat competitions when wheat fields infest with wild oat. Although the wheat yield loss was increased by N application, a such reduction was more recorded at N application than multistage-applied N. Greater knowledge of the effect of N on weeds and crop grown in competitive mixtures may allow a better understanding of why differences occurred among previous studies and aid development of fertilization strategies to reduce weed competition with crops.

Evaluating the Effect of Dry Residues Plant Hairy Vetch (Vicia vilosa Roth) And Plant Probiotics on Reducing the Infection of Branched Broomrape (Orobanche ramosa) In Tomato (Solanum lycopersicum Mill)

I. Nosratti; s. amiri; Gh. Mohammadi; D. Kahrizi; R. Sharifi

Volume 40, Issue 3 , December 2017, , Pages 65-76

https://doi.org/10.22055/ppd.2017.19792.1406

Abstract

Abstract Background and Objectives Tomato (Solanum lycopersicum Mill) is one the most important economic crop in the world and Iran. Broomrape is the main constrain of tomato ... Read More Abstract Background and Objectives Tomato (Solanum lycopersicum Mill) is one the most important economic crop in the world and Iran. Broomrape is the main constrain of tomato production. Some Orobanche species such as O.cumana or O. crenata are specialist in parasites of a small group of genera or species, while others have a much broader spectrum of hosts as is the case of O. ramosa. The available control methods have not proven to be as effective, economical and applicable as desired; thus, the only way to cope with the weedy root parasites is through an integrated approach, employing a variety of measures like resistant cultivars, plant probiotics and allelopathic plants in a concerted manner. Materials and methods Hence the aim this study was to determining the susceptibility of various cultivars of tomato to infection by O. ramosa and effect of allelopathic hairy vetch and plant probiotics on reducing the O. ramosa invasion. Greenhouse experiment was conducted in the greenhouse of Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran in 2016. Treatments were different tomato cultivars including Karoon, Aras, Super strain-B and Sivand, allelopathic hairy vetch cluster, bacteria isolates, including INR7, P2, and E11. The soil of each pot was contaminated with 20 mg seed of O. ramosa. At the termination of the experiment, the number and weight of tomato fruits, dry weight of roots and aerials parts of tomato plants were recorded. Results Our results showed that although the Sivand was the most susceptible cultivar to O. ramosa infection, Karoon cultivar had the highest to levace to branched broomrape. Results of present study revealed that broomrape biomass was positively correlated to decreased tomato biomass. The presence of allelopathic plant hairy vetch increased tomato weight in presence of branched broomrape. The use of probiotic P2 increased the number and weight of tomato in the presence of O. ramosa, while it had no effect on infection of O. ramosa. However, only INR7 probiotic had some inhibitory effect on branched broomrape infection. Discussion Totally hairy vetch had a significant effect on reducing of O. ramosa infection (up to 100% control). Based on these results, it could be concluded that plant probiotics only increase tomato yield without any dirrectly effect to broomrape residues of hairy vetch probably by releasing allelochemical redused orobanche germination infection

Planting Date Effect on Yield and Yield Component of Three Wheat Cultivars in Competitive With Wild Oat

M. Asadnezhad; M. Farzaneh; M. Meskarbashee

Volume 40, Issue 1 , June 2017, , Pages 55-68

https://doi.org/10.22055/ppd.2016.12431

Abstract

Background and Objectives Wheat cultivars that have suppression potential of weeds besides high yield can be a weed management method in sustainable agriculture. Materials and Methods ... Read More Background and Objectives Wheat cultivars that have suppression potential of weeds besides high yield can be a weed management method in sustainable agriculture. Materials and Methods In order to study the competition ability of some wheat cultivar with wild oats in three planting dates, a field experiment as factorial in complete randomize blocks with three replications was carried out at the Agricultural Research Station of Shahid Chamran University in 2013-2014. In this experiment, the factors included planting dates (16th November, 1st December and 16th December), wheat cultivars (Star, Chamran and Virinak) and competition with wild oats (with wild oat, without these weeds). Results The result showed, in the competition status, Star cultivar had a higher grain yield than other cultivars in the first planting date (16th November) whereas, it had no significance different with Star and Chamran in the second planting date (1st December). When the cultivars were planted as monoculture, the highest grain yield belong to Star in the first planting date followed by the second planting data. In this condition, Virinak and Chamran in the first planting date had the lowest grain yields. Effect of the planting date on grain yield was the same trend as grain/spike; however, the high correlation with grain/spike (81%) and with thousand grains weight (59%) confirmed it. Three cultivars obtained the highest of competition index in 1st December. Although the competition and planting date resulted in decrease of grain yield, according to this investigation, the best planting date was determined 16th November and 1st December for Star cultivar. When the planting was delayed (16th December), virinak was a better choice. Discussions According to the different growth, competitive and morphological characteristics of wheat cultivars, their responses varied in different planting dates in competition against wild oats. The grain yield of Chamran, Star and Virinak cultivars decreased 27, 25 and 23 respectively by competition with wild oats. In this respect, the dry matter of planted wild oats on 1st December than the former and latter planting dates was further damaged by every three wheat cultivars (Star, Chamran and Virinak) besides higher grain yield of wheat cultivars whereas the climatic conditions of this year with previous years differed, suggesting wheat planting with short delay as an agronomy method was assayed in the different years with regard to temperature and hydrothermal effect on wild oats germination and growth in comparison with wheat.

Evaluating the effects of water quality and ammonium sulfateon glyphosate herbicide efficiency in weed control of a barberry (Berberis vulgaris) garden

P. Yadegar Khosravieh; S.V. Eslami; M. Jami ALahmadi; E. Zand

Volume 37, Issue 4 , March 2014, , Pages 23-34

Abstract

To evaluate the effects of water quality and adjuvant (ammonium sulfate) in glyphosate herbicide efficiency, a factorial experiment based on RCBD with three replications was conducted ... Read More

Determination of critical period of weed control in corn (Zea mays L.) in Ahvaz region

A. Gerami; S.A. Siadat; A.M. Bakhshandeh; Ghodratallah Fathi; K. Alami Saeid

Volume 36, Issue 1 , June 2013, , Pages 39-49

Abstract

In order to determine the critical period of weed control in grain corn (Zea mays L.), a field study was conducted at the Ramin University ofAhvaz Research Field in 2009. The experiment ... Read More

Effect of chemical, organic and biological fertilizers systems on yield and yield components of wheat genotypes (T. aestivum and T. durum) in Ahvaz conditions

A. Lotfi Jala Abadi; S.A. Siadat; A. Bakhsandeh; Ghodratallah Fathi; K. Alemi Saied

Volume 36, Issue 1 , June 2013, , Pages 103-116

Abstract

In order to study the effect of fertilizer systems and cultivars on wheat production, an experiment was conducted in Agriculture and Natural Resources University of Ramin, North of ... Read More

Effect of Integrated Weed Management Systems on Yield Quality and Quantity of Sugarcane in Khouzestan

A H; A A; H H

Volume 35, Issue 3 , December 2012, , Pages 55-68

Abstract

In order to evaluate the effect of integrated weed management on the yield quality and quantity of Sugarcane, variety CP69, a field experiment was conducted during 2009-2010 at the ... Read More

Volume 47 (2024)

Volume 46 (2023)

Volume 45 (2022)

Volume 44 (2021)

Volume 43 (2020)

Volume 42 (2019)

Volume 41 (2018)

Volume 40 (2017)

Volume 39 (2016)

Volume 38 (2015)

Volume 37 (2014)

Volume 36 (2013)

Volume 35 (2012)

Volume 34 (2011)

Volume 33 (2010)

Volume 32 (2009)

Main Subjects = A: Weed Sciences

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract