بررسی برخی از صفات مورفولوژیکی و عملکرد دانه سویا تحت تنش کم‏‎آبیاری و محلول‌پاشی اسیدهای آمینه

با توجه به این‏‎که ایران جز مناطق خشک و نیمه‏‎خشک محسوب می‏‎شود، مدیریت آب در بخش کشاورزی از اهمیت ویژه‏‎ای برخوردار است. به‏‎منظور بررسی اثر تنش خشکی بر سویا، آزمایشی در دو سال زراعی 1397 و 1398 در مزرعه دانشکده کشاورزی دانشگاه تربیت مدرس اجرا شد. آزمایش به‏‎صورت سه سطح آبیاری (آبیاری کامل، کم‏‎آبیاری متوسط و کم‏‎آبیاری شدید) در کرت‌های اصلی و محلول‏‎پاشی اسیدهای آمینه مختلف در شش سطح (لوسین، والین، سیستئین، اسیدهای آمینه تجاری و بدون محلول‏‎پاشی) به‏‎عنوان کرت‏‎های فرعی در نظر گرفته شدند. با توجه به نتایج مشخص شد در کم‏‎آبیاری شدید، برخی از صفات مورفولوژی سویا مانند صفات ارتفاع بوته، وزن تر و خشک برگ و ساقه، وزن تر و خشک غلاف، شاخص سطح برگ، تعداد غلاف در بوته، تعداد دانه در غلاف، تعداد دانه در بوته و عملکرد دانه کاهش معنی‏‎داری نسبت به آبیاری مطلوب نشان می‏‎دهند. هم‏‎چنین در کم‏‎آبیاری شدید عملکرد دانه کاهش 16/26درصدی و معنی‏‎داری نسبت به آبیاری کامل داشت. نتایج نشان داد با محلول‏‎پاشی بوته‏‎ها، عملکرد دانه سویا افزایش معنی‏‎داری داشت و هم‏‎چنین سیستئین و والین در بین اسیدهای آمینه کاربردی، بیشترین تاثیر را بر عملکرد دانه داشتند. با توجه به نتایج پژوهش به‏‎منظور جلوگیری از کاهش عملکرد بهتر است از کم‏‎آبیاری شدید در حد امکان استفاده نشود و هم‏‎چنین در صورت لزوم از محلول‏‎پاشی اسید آمینه والین و سیستئین به‏‎منظور تاثیر مثبت روی عملکرد گیاه سویا، استفاده شود.

investigating some morphological traits and yield of soybean under deficit irrigation and foliar application of amino acids

introduction: the growth and development of crops are permanently affected by various environmental factors, and environmental stress is one of the most important factors that reduce the yield of crops in the world. drought is one of the most important abiotic stresses in plants. drought stress also aggravates the effect of other stresses or causes them to appear. considering that iran is one of the dry and semi-arid regions, water management in the agricultural sector is of particular importance. in this regard, the aim of this research was to investigate the effect of deficit irrigation and foliar application of amino acid on some morphological traits and grain yield of soybean.materials and methods: the experiment was carried out in the two years of 2018 and 2019 in the farm of the faculty of agriculture of tarbiat modares university. this research was designed and implemented as a split plot based on a randomized complete block design with three replications. the experimental factors include three irrigation levels (full irrigation, moderate deficit irrigation and severe deficit irrigation), which were placed in the main plots, and foliar spraying of amino acids with five levels (leucine, valine, cysteine, commercial amino acids, without foliar spraying) as sub-plots were considered. the number of experimental plots was 54. in each repetition, three main plots were created at a distance of one meter from each other and 6 sub-plots were created inside each main plot. the distance between the plants on the cultivated rows was 8 cm. some morphological traits and grain yield of soybean were measured.results and discussion: based on the results of the interaction of the year in the irrigation regime, the height of the plant decreased in each year with the decrease in irrigation, but this decrease was not significant in the first year. the results showed that by spraying the plants with amino acids, the height of the soybean plant increased significantly compared to the control, and among the amino acids, commercial amino acid (91.77 cm) and cysteine (91.06 cm) had the greatest effect on the height of the plant, although there was no significant difference with other amino acids. the highest leaf area was related to the plants sprayed by valin in the second year. the results showed that in each year, with the application of amino acids, the leaf area of the soybean plant increased significantly compared to the control. valine amino acid with the greatest effect on leaf dry weight increased it by 29.57% compared to the control treatment. the results showed that foliar spraying of all four types of amino acids had a significant increasing effect on the dry weight of the stem compared to the control, and cysteine had a 34.6% increase in the dry weight of the stem compared to the control, although there was no significant difference with other amino acid treatments. the results showed that in both years, with the application of amino acids, the wet weight of pods increased compared to the control, and it was significant in the second year. the three interaction effects of the year in the irrigation regime in amino acids had a significant effect only on the characteristics of stem wet weight and pod dry weight.conclusion: the results indicated that foliar spraying of amino acids had a positive increasing effect on morphological traits. valine and cysteine amino acids had the most significant positive effect on grain yield of soybean.