Document Type : Research Paper

Authors

1 Assistant Professor, Sugar Beet Seed Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran

2 M.Sc. of Plant Biotechnology, Agricultural Biotechnology Research Institute of Iran, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran

Abstract

Abstract
Introduction
Food security is affected by many factors, including increased demand, high input prices, soil degradation, the need to limit greenhouse gas emissions, and increased competition for land and non-potable water. In addition, climate change is expected to have an increasing impact on performance, with statistical analysis of product performance indicating that such an event is taking place. The purpose of plant breeding programs is to develop new varieties with improved characteristics such as yield and nutritional quality. Sugar beet is a root crop specific to temperate regions mainly produced as a sucrose source for human diets. Sugar beet can be planted on any continent except Antarctica, but it performs best in temperate climates. Worldwide production of sugar beet is relatively stable. Studies on the effect of environment and year on sugar beet yield has a long history in Iran. However, it is difficult to achieve a general conclusion due to the dispersion and disparity in the results of various studies. In this study, a meta-analysis method was used to integrate and re-analyze results of independent experiments to achieve a single result.
 
Materials and Methods
Twenty-one experiments carried out at Motahhari Research Station in Karaj, Iran during 2002-17
were evaluated. The effect size was calculated and studies were weighted by replication. Then, the mean effect sizes were estimated followed by confidence intervals, effect size back-transforming and graphs were designed.
 
Results and Discussion
Among studied years, the highest mean root yield of 89.5, 89.1 and 87.8 t ha-1 were obtained in 2018, 2006 and 2012, respectively. Results integration showed that in 2006, 2011, 2014, and 2017, root yield of sugar beet increased by 19.2%, 2.2%, 2.8% and 18.6%, respectively. Different parameters can be used to describe improved agricultural productivity; one of which is the yield increase over time attributed to advances in plant breeding as well as changes in crop operations and environmental conditions (especially climate). Another parameter is the yield potential of a crop described as the performance of a cultivar grown in compatible environments without nutrient and water restrictions and under the effective control of pests, diseases, weeds, and other stresses. Meta-analysis results showed that increase in sugar yield of sugar beet genotypes was similar to the root yield, with the difference that in the years 2006, 2011, 2014 and 2017, variations in percentage was less than root yield. One of the most important results in this study was the illustration of the reduction in slope of negative relationship between root yield and sugar yield in commercial cultivars.
 
Conclusion
In this study, trials were performed under normal conditions and in a disease-free environment. According to the obtained results, use of meta-analysis method in breeding programs to estimate the effect of year on performance along with other statistical methods is recommended.

Keywords

Main Subjects

References
Akeson, W. R. (1981). Relationship of climate and sucrose content of sugarbeet roots. Journal of the ASSBT, 21(1), 27-40.
Barker, H. L., Holeski, L. M., & Lindroth, R. L. (2019). Independent and interactive effects of plant genotype and environment on plant traits and insect herbivore performance: A meta‐analysis with Salicaceae. Functional Ecology, 33(3), 422-435.
Bengtsson, J., Ahnsrtom, J., & Weibull, A. (2005). The effects of organic agriculture on biodiversity and abundance: a meta-analysis. Journal of Applied Ecology, 42(2), 261-269.
Fasahat, P., Aghaeezadeh, M., Kakueinezhad, M., & Jabbari, L. (2020). A meta-analysis of genotype× environment interaction on sugar beet performance. Biometrical Letters, 57(2), 221-236.
Fasahat, P., Aghaeezadeh, M., Jabbari, L., Hemayati, S. S., & Townson, P. (2018). Sucrose accumulation in sugar beet: from fodder beet selection to genomic selection. Sugar Tech, 20(6), 635-644.
Fasahat, P., Muhammad, K., Abdullah, A., Rahman, B. M. A., Siing, N. M., Gauch, J. H. G., & Ratnam, W. (2014). Genotype × environment assessment for grain quality traits in rice. Communications in Biometry and Crop Science, 9(2), 71-82.
Gurevitch, J., & Hedges, L. V. (1999). Statistical issues in ecological Meta-Analysis. Ecology, 80(4), 1142-1149.
Hedges, L. V. (1992). Modeling publication selection effects in meta-analysis. Statistical Science, 7(2), 246-255.
Hedges, L. V., Gurevitch, J., & Curtis, P. S. (1999). The meta‐analysis of response ratios in experimental ecology. Ecology, 80(4), 1150-1156.
Hoffmann, C. M., & Kenter, C. (2018). Yield potential of sugar beet–have we hit the ceiling?. Frontiers in Plant Science, 9, 289.
Huang, S., Zeng, Y., Wu, J., Shi, Q., & Pan, X. (2013). Effect of crop residue retention on rice yield in China: A meta-analysis. Field Crops Research, 154, 188-194.
Jaggard, K. W., Qi, A., & Ober, E. S. (2010). Possible changes to arable crop yields by 2050. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 365(1554), 2835-2851.
Khaliliaqdam, N., Hasanai, R., & Mir-Mahmoodiand, T. (2018). Meta-analysis of some effective factors on wheat production in Iran. Crops Improvement, 20(1), 191-204.
King, B. A., & Tarkalson, D. D. (2017). Irrigated sugarbeet sucrose content in relation to growing season climatic conditions in the northwest US. Journal of Sugar Beet Research, 54(1&2), 60-74.
Linquist, B. A., Liu, L., Van Kessel, C., & Van Groenigen, K. J. (2013). Enhanced efficiency nitrogen fertilizers for rice systems: Meta-analysis of yield and nitrogen uptake. Field Crops Research, 154, 246-254.
Loel, J., Kenter, C., Marlander, B., & Hoffmann, C. M. (2014). Assessment of breeding progress in sugar beet by testing old and new varieties under greenhouse and field conditions. European Journal of Agronomy, 52, 146-156.
McGrath, J. M., & Townsend, B. J. (2015). Sugar beet, energy beet, and industrial beet. In Industrial Crops. New York, NY: Springer.
Munnich, M., Khiaosa-Ard, R., Klevenhusen, F., Hilpold, A., Khol-Parisini, A., & Zebeli, Q. (2017). A meta-analysis of feeding sugar beet pulp in dairy cows: Effects on feed intake, ruminal fermentation, performance, and net food production. Animal Feed Science and Technology, 224, 78-89.
Niazian, M., Rajabi, A., Amiri, R., Orazizadeh, M.R., & Sharifi, H. (2012). Surveying the relations among traits affecting root yield and sugar content in o-type lines of sugar beet for winter sowing. Journnal of Plant Production, 35(2), 115-135. [In Farsi]
Orazizadeh, M. R. (2007). Evaluation of the quality and quantity of monogerm commercial sugar beet varieties in different climates of the country. Final Report, Sugar Beet Seed Institute, pp. 1-56. [In Farsi]
Orazizadeh, M. R. (2008). Comparison of the quality and quantity of monogerm commercial sugar beet varieties in different climates of the country. Final Report, Sugar Beet Seed Institute, pp. 1-72. [In Farsi]
Orazizadeh, M. R. (2009). Comparison of the quality and quantity of monogerm and multigerm commercial sugar beet varieties in different climates of the country. Final Report, Sugar Beet Seed Institute, pp. 1-122. [In Farsi]
Orazizadeh, M. R. (2010). Comparison of the quality and quantity of monogerm and multigerm commercial sugar beet varieties in different climates of the country. Final Report, Sugar Beet Seed Institute, pp. 1-91. [In Farsi]
Orazizadeh, M. R. (2011). Comparison of the quality and quantity of monogerm and multigerm commercial sugar beet varieties in different climates of Iran. Final Report, Sugar Beet Seed Institute, pp. 1-75. [In Farsi]
Orazizadeh, M. R. (2012). Comparison of quality and quantity of monogerm and multigerm commercial sugar beet varieties in different climates of Iran. Final Report, Sugar Beet Seed Institute, pp. 1-68. [In Farsi]
Qaemi, A., & Qolizadeh, R. (2004). Investigation of some physiological and morphological indices influencing qualitative and qualitative yield increase in sugar beet. Final Report, Sugar Beet Seed Institute, pp. 1-41. [In Farsi]
Ranji, Z., & Ebrahimian, H. R. (2006). Investigation of quality and quantity of native foreign commercial sugar beet varieties. Final Report, Sugar Beet Seed Institute, pp. 1-69. [In Farsi]
Ranji, Z., & Ebrahimian, H. R. (2007). Investigation on quality and quantity of native foreign monogerm commercial sugar beet varieties. Final Report, Sugar Beet Seed Institute, pp. 1-42. [In Farsi]
Schneider, K., Schafer-Pregl, R., Borchardt, D. C., & Salamini, F. (2002). Mapping QTLs for sucrose content, yield and quality in a sugar beet population fingerprinted by EST-related markers. Theoretical and Applied Genetics, 104(6-7), 1107-1113.