Introduction

Weeds are one of the most important factors limiting the wheat (Triticum aestivum L.) growth and Production; among them the invasive plants play an important role in the formation of ecosystem disturbances and a threat to biodiversity in the 21st century C. balsamita Lam. is a problematic weed spreading in the country's winter grain fields. Due to the limitations of physical and mechanical methods, using chemical methods is considered the most important method to control weeds in wheat fields. Given the invasiveness of this weed, as well as the incompatibility of applying some herbicides with the sensitive stage of weed, the escape of this weed from chemical management in wheat fields, since mechanical methods can be used less in combination with other management methods in grain crops such as wheat, so, it is essential to obtain results from this experiment and provide solutions to overcome these problems for effective chemical control of C. balsamita Lam.



Materials and Methods

In order to select the best herbicide(s) among common wheat-selective post-emergence herbicides to control the invasive weed of (C. balsamita Lam.), a factorial pot experiment was conducted based on a completely randomized design with three replications in the spring of 2024 in the outdoor at the Faculty of Agriculture of Razi University, Kermanshah, Iran. Herbicides included of 2, 4-D + MCPA, bromoxynil + MCPA, dicamba + 2, 4-D, bentazone, tribenuron-methyl, iodosulfuron-methyl sodium + mesosulfuron-methyl and iodosulfuron-methyl sodium + mesosulfuron-methyl + diflufenican, which were used in five concentrations including 0, 0.125, 0.25, 0.50, and 1 times the recommended dosage at two growth stages of C. balsamita Lam.(2 to 4 and 6 to 8 leaves). 30 d after herbicide application, visual assessment of herbicides affection on weed plants was conducted according to European Weed Research Council (EWRC) method. In addition dry and fresh weight as well as plant height of weed plants which remained after spraying in pots was measured and the differentiation of above mentioned traits compared with the untreated control was calculated.



Results and Discussion

Dicamba + 2, 4-D, bentazone and bromoxynil + MCPA were among the best herbicides with 100% control (dry mass reduction) of (C. balsamita Lam.) compared with the untreated control, in 2-4 and 6-8 leaf stages as well as tribenuron methyl in 2-4 leaf growth stage. 2, 4-D + MCPA and iodosulfuron-methyl-sodium + mesosulfuron-methyl + diflufenican herbicides were relatively good herbicides to eliminate weed (dry mass reduction) in 2-4 leaf stage by 86 and 72%., and in 6-8 leaf stage by 96 and 62%, respectively. dicamba + 2, 4-D, bentazone and bromoxynil + MCPA were among the best herbicides with 100% plant height reduction. and 2, 4-D + MCPA was included in the relatively good herbicide with % plant height reduction of C. balsamita Lam.̕by 88% and 95% at both growth stages (2-4 and 6-8 leaves stage), respectively. Dicamba + 2, 4-D, bentazone and bromoxynil + MCPA were among the best herbicides with 100% fresh weight reduction of C. balsamita Lam. and 2, 4-D + MCPA and tribenuron methyl was included in the relatively good herbicide with fresh weight reduction percentage of C. balsamita Lam.̕by 82% and 95% and by 85% and 100% at both growth stages (2-4 and 6-8 leaves stage), respectively. Bentazone and bromoxynil + MCPA were among the best herbicides in visual assessment. The results showed that dicamba + 2, 4-D, bentazone and bromoxynil + MCPA in the recommended dose of these herbicides in both leaf growth stages of C. balsamita Lam. caused had 100% weed control compared with the untreated control.



Conclusion

As a result, the use of relatively common herbicides such as dicamba + 2, 4-D, bentazone and bromoxynil + MCPA, which have high potency in suppressing C. balsamita Lam., can be implemented in infected areas that is a good solution and will prevent the invasion of (C. balsamita Lam.) into the country's fields. The prevalence of C. balsamita Lam. is not due to the weak efficiency of common herbicides (tribenuron methyl and 2, 4-D) but rather to the mismatch between the timing of appropriate herbicide control and the sensitive growth stage of weed.