تجزیه به مولفه‌های اصلی و علّیت صفات آگرومورفولوژیک ژنوتیپ‌های نخود کابلی (cicer arietinum l.) در کشت دیم بهاره و پاییزه

جهت ارزیابی ماهیت و نوع روابط موجود در بین برخی صفات زراعی و عملکرد دانه نخود کابلی، 108 ژنوتیپ و رقم به‌همراه چهار رقم شاهد در قالب طرح آزمایشی آگمنت تحت دو شرایط تنش سرما (کشت پاییزه) و بدون تنش (کشت بهاره) در مرزعه تحقیقاتی موسسه تحقیقات کشاورزی دیم کشور مورد مطالعه قرار گرفتند. بر اساس تجزیه همبستگی ساده مشخص گردید که در هر دو شرایط کشت بهاره و پاییزه صفات تعداد غلاف کل، تعداد غلاف‌های تک‌‌بذری و عملکرد زیست‌توده بیشترین همبستگی را با عملکرد دانه داشتند. در کشت بهاره تعداد غلاف کل اثر مستقیم زیادی بر عملکرد دانه داشت، ولی اثر غیرمستقیم تعداد غلاف کل از طریق وزن 100 دانه بر عملکرد دانه منفی بود. در کشت پاییزه با وجود اثر مستقیم بالای تعداد غلاف کل بر عملکرد دانه، به دلیل اثر غیرمستقیم منفی از طریق تعداد غلاف پوک، ضریب همبستگی ساده تعداد غلاف کل با عملکرد دانه بسیار زیاد نبود. در کشت بهاره ژنوتیپ های 108 ،63، 65 و 99 بیشترین تعداد غلاف کل، تعداد غلاف تک‌بذری، زیست‌توده و عملکرد تک بوته و ژنوتیپ‌های 55، 76، 81، 82، 84، 85 و 88 بالاترین وزن 100 دانه و طول و قطر غلاف را دارا بودند. در کشت پاییزه، ژنوتیپ‌های 87 و 22 مقدار زیست‌توده و عملکرد تک‌بوته بیشتر، ژنوتیپ‌های 45 و 65 تعداد غلاف کل و تعداد غلاف تک‌بذری بیشتر، ژنوتیپ 89 تعداد غلاف کل و زیست‌توده بیشتر و ژنوتیپ 94 تعداد غلاف کل، تعداد غلاف تک‌بذری، زیست‌توده و عملکرد تک‌بوته بیشتری نشان دادند. در هر دو کشت پاییزه و بهاره، تعداد غلاف کل بیشترین اثر مثبت و مستقیم را بر عملکرد دانه داشت. بنابراین توصیه می‌شود در برنامه‌های به‌نژادی در راستای افزایش عملکرد دانه در ژنوتیپ‌های نخود در هر دو شرایط تنش سرما و بدون تنش، گزینش بر اساس تعداد غلاف کل در بوته صورت پذیرد که صفتی قابل رویت بوده و اندازه‌گیری آن ساده است.

principal component and path analysis of agro-morphological traits of kabuli chickpea genotypes (cicer arietinum l.) under dryland spring-planting and autumn-planting

introduction legumes are the most economically important food source for humans due to their protein richness, especially in developing and underdeveloped countries. chickpea yield in spring-planting under dryland cropping decreases due to increasing temperature and day length and the occurrence of end-season drought and exposure to important pest’s activity. in autumn-planting, early flowering, escaping from pests and optimal use of annual rainfall help to significantly increase in grain yield. increasing the growth period during autumn planting has been found to result in taller plant height, making mechanical harvesting more feasible. the success of a plant breeding program relies on implementing a suitable selection design that takes into account both correlated and non-correlated relationships. recently, a significant positive correlation has been observed between grain yield and several traits such as the number of pods, number of seeds, 100-kernel weight, and harvest index in chickpea. these traits were also found to have a direct and significant effect on chickpea grain yield. additionally, there was a high direct effect observed for pod number, number of seeds, 100-kernel weight, and single-seed weight on chickpea grain yield.materials and methodsthis research was conducted on 112 chickpea genotypes in dryland spring-planting (non-cold stress condition) and autumn-planting (cold stress) based on augmented design in dryland agricultural research institute located in maragheh. total pods number, number of empty pods, number of tow-seed pods, plant height, first pod height from soil level, number of pods with one seed, days to maturity initiation, days to 90% maturity, 100-kernel weight, pod diameter, pod length, biomass, harvest index, fertility percent and single-plant yield were meassured. the correlation analysis, stepwise regression and path analysis, and principal component analysis were used for identifying the relationships among agro-morphological traits. results and discussion in autumn-planting condition grain yield positively correlated with all traits except days to 90% maturity, but in spring-planting condition the correlation between grain yield and first pod height, days to maturity initiation, days to 90% maturity, 100-kernel weight, pod diameter and pod length were not significant. in spring-planting, 100-kernel weight and total pods number were negatively correlated. in both spring and autumn-planting, the 100-kernel weight showed a significant positive correlation with pod diameter and pod length. this indicates that genotypes with larger pods also tend to have larger seeds. furthermore, in autumn-planting, there was a significant positive correlation between pod diameter, pod length, and grain yield. however, these correlations were not significant in spring-planting. stepwise regression analysis was performed to assess the factors influencing grain yield in both planting conditions. in spring-planting, the number of total pods, 100-kernel weight, fertility percent, and the number of two-seed pods were found to have direct and significant effects on grain yield. on the other hand, in autumn-planting, the number of total pods, pod length, number of empty pods, 100-kernel weight, and the number of two-seed pods were included in the final model as predictors of grain yield. these results suggest that these factors play a crucial role in determining grain yield in their respective planting conditions. in spring-planting, the genotypes 108, 63, 65 and 99 had the highest number of total pods, number of single pods, biomass and plant yield and genotypes 55, 76, 81, 82, 84, 85 and 88 had the highest weight of 100-kernel, pod length and pod diameter.