پديد آورندگان :
ليموچي، كاوه دانشگاه علوم كشاورزي و منابع طبيعي - دانشكده كشاورزي - گروه مهندسي توليد و ژنتيك گياهي، خوزستان، ايران , سيادت، عطا اله دانشگاه علوم كشاورزي و منابع طبيعي - گروه مهندسي توليد و ژنتيك گياهي، دانشكده كشاورزي، خوزستان، ايران
كليدواژه :
آوند , اكسين , الگوي كاشت , بافت , پرايمينگ , ساليسيليك
چكيده فارسي :
اين پژوهش با هدف تعيين بهترين روش كشت و تيمار هورموني در مواجهه با شرايط شوري پيرامون گياه برنج به صورت كرت هاي دو بار خردشدهدر قالب طرح بلوك هاي كامل تصادفي با سه تكرار در استان خوزستان در دو سال (1397 و 1398) انجام شد.سه شيوه كاشت (خشكه كاري، فشايي و مستقيم يا رايج منطقه)، 16 سطح مختلف هورمون هاي اكسين و سالسيليك اسيد به صورت پر ايمينگ بذري و تيمارهاي مختلف اسپري برگي با مقدار 1 و 2 ليتر در هكتار و زمان هاي اسپري مختلف در مراحل پنجه زني و ظهور خوشه بر ژنوتيپ هاي مختلف برنج مورد بررسي قرار گرفت. نتايج تجزيه مركب نشان داد به غير از اثر متقابل روش كشت در هورمون صفت سطح دستجات آوندي بزرگ در ساير موارد اثرات اصلي و متقابل صفات تفاوت معني داري در سطح احتمال يك درصد وجود دارد. بيشترين سطح دستجات آوندي در روش كشت نشايي به دليل مديريت بهينه و پر ايمينگ با اكسين و سالسيليك اسيد به دليل بيشترين تاثير گذاري بر گياه بدست آمد. همچنين سطح صفات مزبور در ژنوتيپ هاي با مقاومت بيشتر كمتر بود كه مي تواند يكي از سازوكارهاي اصلي گياه به لحاظ افزايش سازگاري و حفظ بيشتر پتانسيل آبي درون گياه تحت تنش شرايط شوري باشد. در نهايت به ترتيب بيشترين سطح دستجات آوندي بزرگ و كوچك با متوسط 12348 و 1928/792 ميكرومتر مربع در ژنوتيپ هاي IR 80508-B-194-3-B و عنبوري قرمز در تيمارهاي گفته شده بدست آمد. سطح دستجات آوندي بزرگ بيشترين همبستگي مثبت و معني دار را با ضريب ** 0/131 باعملكرد دانه به لحاظ سطح بالاي آن در انتقال آب و مواد غذايي دارا بود. نتايج بدست آمده مي تواند يكي از اهداف اصلي در تحقيقات به نژادي و اصلاح ارقام با مقاومت بالاتر به شرايط شوري تحت تأثير تيمارهاي مختلف هورموني و الگوهاي كاشت باشد.
چكيده لاتين :
Xylem vascular bundles area decreases in response towater stress in order to improve water use efficiencyand to maintain plant water potential (Limouchi&Farahvash, 2014). Stresses can decrease vascular bundles area and diameter, which can result in improved water use efficiency and to reduced transpiration.These anatomical changes, in turn, are positively and significantly correlated to grain yield (Limouchi, et al., 2013). Water shortage for rice leads to a reduction in the value of anatomical traitsthat are effective in water retention
and movement such as vascular bundles, contributing to maintaining the amount of water in rice (Dawood, 2016). This study wasaimed to identify the tolerance and sensitivity mechanisms to drought under different irrigation intervals in order
to increase grain yield by examining changes in anatomical characteristics of leaf stamen.
Materials and Methods:
This study was performed using split-split plots in a randomized complete block 2 «Applied Research in Field Crops» Vol 34, No 3, 2021
design with three replications in Khuzestan province with the aim of determining the best planting pattern and hormone treatment of rice in two cropping years (2018 and 2019). Three planting methods (dry planting, seedlings planting, direct or common planting), 16 different levels of auxin and salicylic acid hormones in the form of seed priming and different leaf spray treatments with 1 and 2 liters per
hectare and different spraying times at the tillering stage and the appearance of panicle were applied to different rice genotypes.For measurement of anatomical features, were isolated at the time of ear emergence and flag leaf of the plant after
removal of the terminal and basal segments, cut into 2-3 cm length were taken from the middle part of the flag leaf. For the maintenance of laboratory samples and send them to the formalin-acetic acid-alcohol solution was used.In the laboratory, and a narrow cross section 10×10 mm using a manual method Polystyrene were prepared and stained, the samples after washing with distilled water for 15 minutes
in bleach water and then 20 minutes in Carmen aluminize and finally for 10 to 15 seconds at each of the stages were methyl green staining were washed thoroughly with distilled water. Then samples for preparation of stained slides and pictures were placed on glass slidesand attributes include: the level of large and small vascular bundleswith 10-40 zoom (Micrometers) were measured.
Results and Discussion: Theresults of combined analysis of variance showed that, except for the interaction effect of planting method andhormone treatments for large leaf vascular bundles area, in other treatments, the main and interaction effects of the traits were found to be significant at the probability level of 1%. The highest area level of vascular bundles was obtained with seedling planting due to optimal management and priming with auxin and salicylic acid, which had the greatest effect on the plant. Also, the area level of vascular bundles was lower in genotypes with higher resistance, which can be viewed as one of the main mechanisms
employed by the genotypes in terms of increasing adaptability and maintaining greater water potential within the plant under stressful conditions. Finally, the highest area levels for large and small vascular bundles with an average of 12348 and 1928.792 micrometers were obtained with IR 80508-B-194-3-B genotypes and red amber in the aforementioned treatments, respectively. The surface of large 3 Investigating the ... vascular bundles had the highest positive and significant correlation with grain yield (0.131**), which contributed to higher water and nutrients transfer in grain. The results obtained in this study can be useful to achieve some of the main goals
in breeding research and improvement of cultivars in terms of greater resistance to salinity conditions under the influence of different hormonal treatments and planting patterns.Among the combined hormonal priming treatments of seeds with both growth hormones auxin and salicylic acid, the highest amount of grain yield was observed due to the complementarity of the two growth hormones in
regulating biochemical and morphological reactions of the plant.Time-consuming effects are much more compatible, and we were in the priming method because of creating resistance and accelerating growth.In general, Daniel cultivar had the highest grain yield with an average of 7178.50 kg / ha in seedling culture method with hormonal treatment of priming with auxin and salicylic acid.
Discussion:
The results of this study showed that an increase in hormone and irrigation intervals and thus increased drought severity led to reduced vascular bundles area, which can be a mechanism to maintain water and cells turgidity pressure.
