ارزيابي پرايمينگ بذر با محلول هاي مختلف غذايي در سطوح مختلف تنش آبي بر خصوصيات فيزيولوژيك و عملكرد چغندر قند رقم بذر تك جوانه ژنتيكي

Evaluation of seed priming using nutrient solutions under different water stress levels on growth and yield of monogerm cultivar of sugar beet

اين مطالعه با هدف بررسي تأثير سطوح مختلف آبياري (آبياري پس از 70، 110 و 150 ميلي‌متر تبخير از تشتك) و تيمارهاي مختلف پرايمينگ (شاهد، هيدروپرايمينگ، پرايمينگ با آهن، روي و منگنز) بر جوانه‌زني، رشد و عملكرد چغندرقند در سه تكرار اجرا شد. آزمايش در شرايط آزمايشگاهي به‌صورت طرح كاملاً تصادفي و در مزرعه به‌صورت اسپيلت ­پلات بر پايه طرح بلوك‌هاي كامل تصادفي اجرا گرديد. كم‌آبي كاهش معني‌داري را در عملكرد ريشه و قند چغندرقند باعث شد، با تشديد كم‌آبي، ميزان كاهش در اين دو صفت بيشتر بود. عملكرد ريشه و قند با افزايش دور آبياري از آبياري پس از 70 ميلي‌متر تبخير از تشتك به آبياري پس از 110 و 150 ميلي‌متر تبخير از تشتك به ترتيب 38 و 41.8 درصد كاهش يافت؛ اما پرايمينگ بذرهاي چغندرقند با آهن افزايشي 25.5 و 35.4 درصدي و پرايمينگ بذرهاي چغندرقند با روي افزايشي 25.5 و 34.4 درصدي به ترتيب در عملكرد ريشه و عملكرد قند باعث شد. بيشترين درصد قند نيز در پرايمينگ بذور با آهن و روي به دست آمد. با توجه به همبستگي مشاهده‌شده، از دلايل مهم كاهش عملكرد ريشه و قند چغندرقند در اثر كم‌آبي، كاهش سطح برگ است. بااين‌وجود همچون عملكرد، پرايمينگ تأثير مثبتي بر اين صفت داشت. بيشترين افزايش در سطح برگ مربوط به پرايمينگ روي بود. با توجه به همبستگي‌هاي مشاهده‌شده، بهبود در سرعت جوانه‌زني و درصد جوانه‌زني ناشي از افزايش مقدار جيبرلين و درنتيجه بهبود فعاليت آلفا آميلاز از مهم‌ترين دلايل افزايش رشد و عملكرد چغندرقند مي‌تواند باشد. در كل مشاهده شد كه پيش‌تيمارهاي آهن و روي بهترين پيش‌تيمارهاي بذري جهت افزايش رشد و عملكرد چغندرقند در شرايط آبياري كامل و كم‌آبي است.

Drought stress is one of the most important environ-mental factors in reduction of growth, development and production of plants. It can be said that it is one of the most devastating environmental stresses. Iran, with an annual rainfall of 240 mm, is classified as one of those dry regions Moisture stress is a limiting factor for crop growth in arid and semi-arid regions due to low and uncertainty precipitation. Water stress due to drought is probably the most significant abiotic factor limiting plant and also crop growth and development. Priming is one of the seed enhancement methods that might be resulted in increased seed performance (germination and emergence) under stress conditions, such as salinity, temperature and drought stress. also Priming is one of the simple and effective methods in decreasing drought effect on plants. This research had don in order to investigate effect of different irrigation regimes (irrigation after 70, 110 and 150mm evaporate from evaporate basin)and different priming treatments ( control, hydropriming, priming with iron, zin and manganese) on growth and yield of sugar beet in three replication as split plot based on complete block design. Based of results drought decreased root and sugar yield.increase in water shortage caused more reduction. Root and sugar yield decreased 38 and 41.8 % due to irrigation after 110mm evaporate from evaporate basin and irrigation after 150mm evaporate from evaporate basin than irrigation after 70mm evaporate from evaporate basin. But priming also increased this two traits. Seed priming with iron caused 25.5 and 35.4 % increament and Seed priming with zinc caused 25.5 and 34.4 % increment in root yied and sugar yield respectively. Other priming methods did not had any effect on this traits. Highest sugar content also obtained in iron and zinc priming. But water shortage also decreased growth properties of sugaar beet such as leaf area and biomas, but priming had posetive effect on most of growth and reproductive traits of sugar beet.in this investigation priming in water shortage also caused an increase in most of traits. Highest wet biomass, root length and leaf wet weight observed in irrigation after 70 mm evaporate from evaporate basin and priming with iron, Least values observed in irrigation after 150 mm evaporate from evaporate basin and without priming. Thus this investigation shows the importance of priming in decreasing drought effect and increasing growth and yield of sugar beet in full rrigation and water shortage. Over and manganese water treatment effect on percent sugar, sugar yield and sugar beet root yield was not. The largest increase in leaf area was the priming on, but the highest sugar content, sugar yield and root yield in terms of sugar beet seed priming with iron and zinc were obtained and statistically significant difference was observed between these traits. In general, it was observed that the iron treatments and the best pre-treatments to enhance growth and yield of sugar beet seed under irrigation and dehydration. By step by step regression analysis three trait of root yield, sugar percent and dry biomass entered as effective traits on sugar yield that explain 99 % of changes. Root yield was the first trait that entered the model.