ارزیابی عملکرد و اجزاء عملکرد اکوتیپ‌های مختلف سیاهدانه (nigella sativa l.) به تاریخ کاشت‌ در گرگان

به منظور ارزیابی اکوتیپ های مختلف سیاهدانه (nigella sativa l.) در پاسخ به تاریخ کاشت، آزمایش مزرعه ای با چهار تاریخ کاشت در سال زراعی 1399-1400 در شهرستان گرگان به اجرا در آمد. آزمایش به‌صورت کرت های خرد شده در قالب طرح بلوک های کامل تصادفی در سه تکرار صورت گرفت که در آن چهار تاریخ کاشت 28 آذرماه، 28 دی ماه، 28 بهمن ماه و 28 اسفندماه به عنوان فاکتور اصلی و 13 اکوتیپ (جمع‌آوری شده از نقاط مختلف ایران) به عنوان فاکتور فرعی در نظر گرفته شدند. در این تحقیق، صفات ارتفاع بوته، تعداد شاخه در بوته، تعداد فولیکول در بوته، تعداد دانه در فولیکول، وزن هزار دانه و عملکرد دانه اندازه‌گیری شد. نتایج نشان داد که با تاخیر در کاشت، کلیه صفات اندازه گیری شده کاهش یافت. بیشترین عملکرد دانه از تاریخ کاشت اول (1245 کیلوگرم در هکتار) حاصل شد. همچنین از اکوتیپ های خواف، سرایان، بجستان، زابل و اصفهان بیشترین عملکرد دانه به‌دست آمد. با تاخیر در کاشت، عملکرد دانه اکوتیپ های پرعملکرد به‌صورت خطی کاهش یافت (9-8 کیلوگرم در هکتار به‌ازای هر روز تاخیر در کاشت)، با این تفاوت که کاهش عملکرد دانه در اکوتیپ بجستان (5.8 کیلوگرم در هکتار به‌ازای هر روز تاخیر در کاشت) کمتر از سایر اکوتیپ ها بود که بیانگر سازگاری بالای این اکوتیپ به تاریخ کاشت و شرایط محیطی گرگان می باشد. همچنین همبستگی مثبت و معنی‌داری بین عملکرد دانه با صفات ارتفاع بوته (0.73)، تعداد شاخه در بوته (0.56)، تعداد فولیکول در بوته (0.83)، تعداد دانه در فولیکول (0.84) و وزن هزار دانه (0.55) وجود داشت. به‌طور کلی، نتایج این تحقیق نشان داد که تاریخ کاشت و اکوتیپ تاثیر معنی داری بر عملکرد دانه سیاهدانه دارند و ازاین‌رو، توصیه می شود که برای حصول عملکرد دانه بالاتر در گرگان، اکوتیپ های پرعملکرد در آذرماه کاشت شود و برای تایید نهایی آزمایشات تکمیلی در این منطقه صورت گیرد.

evaluation of yield and yield components of different ecotypes of black cumin (nigella sativa l.) to planting date in gorgan

introductionthe use of medicinal plants has been done since ancient times and may even be considered the origin of modern medicine. medicinal plants are a source of biomolecules with therapeutic potential and as a lead to develop new drugs. black cumin (*nigella sativa* l.), often referred to as a &miracle herb,& is a medicinal plant that has been used worldwide for centuries in the treatment and prevention of diseases such as cancer and diabetes. additionally, it has been valued as a spice and flavoring agent in products like bread and sweets. various factors influence the growth and yield of black cumin per unit area, with planting date being particularly significant. the timing of planting affects environmental conditions during the plant’s growth stages, influencing the rates of vegetative and reproductive growth, and ultimately impacting yield. therefore, selecting the appropriate planting time is crucial for the successful cultivation of any crop, including black cumin. the aim of this research is to determine the most suitable planting date of black cumin for this plant and the response of different ecotypes of this medicinal plant to the planting date in the weather conditions of gorgan city.materials and methodsin order to evaluate different ecotypes of black cumin in response to planting date in gorgan, a field experiment with four planting dates was carried out in the cropping year of 2020-2021 at the research farm of gorgan university of agricultural sciences and natural resources, iran. the experiment was carried out in the form of split plots based on completely randomized block statistical design with three replication, in which four planting dates were 18th december, 17th january, 16th february and 18th march as the main plot and thirteen ecotypes (such as tafaresh, gardmiran, razan, hamedan, arak, esfahan, semirom, eqlid, ashkazar, zabol, bajestan, sarayan and khaf) with 3 replication were considered as sub-plot. in this research, the attributes of plant height, number of branches per plant, number of follicles per plant, number of grain per follicle, weight of 1000 grains and grain yield were measured. after harvesting, measurements were taken and then the data were analyzed with sas 9.4 statistical software and means comparison was done with lsd’s test in significance at 5% probability level. graphs were prepared using excel software.results and discussionthe results showed that the interaction effects of planting date and ecotype on plant height, number of branches per plant, number of capsules per plant, number of grains per capsule and 1000- grain weight were significant. however, the main effects of planting date and ecotype on grain yield were significant, and the interaction effects were not significant. with the delay in planting, all measured traits decreased. the highest grain yield was obtained from the first planting date (december 18) with 1245 kg per ha. the highest grain yield was obtained from khaf (1245 kg.ha-1), sarayan (1179 kg.ha-1), bajestan (1156 kg.ha-1), zabol (1141 kg.ha-1) and esfahan (1117 kg.ha-1) ecotypes. in contrast, the lowest grain yield was obtained from the fourth (march 18) planting date with 694 kg.ha-1. the lowest grain yield was obtained from arak and gardmiran ecotypes with 903 and 890 kg.ha, respectively. with the delay in planting, the grain yield of high-yield ecotypes decreased linearly (8-9 kg.ha for each day of delay in planting), with the difference that the decrease in grain yield in the bajestan ecotype (5.8 kg.ha for each day of delay in planting) was less than other ecotypes, which indicates the high adaptability of this ecotype to the planting date and environmental conditions of gorgan.