پديد آورندگان :
ارشادي منش، خسرو دانشگاه كردستان - دانشكده كشاورزي , سي و سه مرده، عادل دانشگاه كردستان - دانشكده كشاورزي - گروه كشاورزي , حسين پناهي، فرزاد دانشگاه كردستان - دانشكده كشاورزي - گروه زراعت و اصلاح نباتات
كليدواژه :
تنش خشكي , شاخص هاي رشد , گندم , مرحله رشد
چكيده فارسي :
به منظور مطالعه روابط شاخص هاي رشد لاين هاي اميدبخش گندم نان با عملكرد آنها در آزمايش جداگانه در شرايط فارياب و ديم در قالب طرح بلوك هاي كامل تصادفي در ايستگاه تحقيقات كشاورزي اسلام آباد غرب در سال زراعي 98-1397 اجرا شد. در هر آزمايش تعداد 9 لاين انتخابي به همراه 2 رقم به عنوان شاهد ارزيابي شدند. شرايط ديم در مقايسه با شرايط فارياب باعث كاهش عملكرد دانه، عملكرد بيولوژيك، عملكرد كاه، شاخص برداشت و وزن هزار دانه به ترتيب به ميزان 24/5، 21/2، 18/9 ، 4/2 و 134 درصد در ميانگين لاين ها شد. تنش خشكي سبب كاهش مقدار شاخص هاي LWR ،LAR.NAR ،RGR و SLA به ترتيب به ميزان 29، 17، 6، 3 و 6 درصد در مرحله گلدهي گرديد. همچنين رابطه مثبت و معني داري بين RGR با NAR در تمام مراحل نمونه برداري هر دو آزمايش و با عملكرد بيولوژيك، عملكرد كاه و وزن هزار دانه در برخي مراحل نمونه برداري مشاهده شد. در آزمايش فارياب RGR در مرحله گلدهي همبستگي مثبت و معني داري (00/64 + = r) با LWR داشت. از بين اجزا تشكيل دهنده RGR، مؤلفه NAR داراي همبستگي منفي و معني داري (0/7-= r در مرحله اول نمونه برداري آزمايش فارياب با LAR داشت. همچنين بين اجزاء LAR (يعني LWR و SLA با LAR در تمامي مراحل نمونه برداري رابطه مثبت و معني دار مشاهده شد و در مراحل اول و سوم نمونه برداري نيز، همبستگي شاخص هايSLA (r=+0.663 and r=+0.608) و LAR (r=+0.704 and r=+0.673) با عملكرد دانه در شرايط فارياب مثبت و معني دار بود كه در نهايت اين دو پارامتر به عنوان شاخص هاي مهم رشد و مرتبط با عملكرد دانه شناسايي شدند.
چكيده لاتين :
Introduction:
Wheat, as one of the main constituents in ensuring food security, provides 20% of the total calories and protein of the world's population. In this regard, recognizing and studying physiological growth indices is very important in analyzing the factors that affect yield and its components. This can aid in determining plant growth stages and evaluating and crop production (Soleymani Fard et al., 2011). Although RGR is the main indicator of growth and determines dry matter accumulation and ultimate yield, its components including NAR, LAR, LWR and SLA appear to be better choice under extreme stress than RGR.
Material and Methods:
This experiment was counducted to study the growth indices and their relationships with the yield of promising bread wheat lines during the 2018-19 cropping year at the Agricultural Research Station of West islamabad, under two separate irrigation and rainfed conditions. The studied genotypes included 9 advanced bread wheat lines along with the two top cultivars, namely, Pishgam and Baharan as a control, which were selected and assessed in a completely randomized block design. Leaf surface was measured using a scanner and ImageJ and Photoshop software packages. The samples were separated into leaves, stems and spikes and their dry weight was calculated after being placed in an oven at 72 °C for 48 hours. Thousand kernel weight was measured by an electronic scale with an accuracy of one thousandth of a gram. Data analysis of variance was performed using SAS software and graphs were also drawn using excel software.
Results and Discussion:
Based on the test results, the rainfed condition decreased grain yield, biological yield, straw yield, thousand kernel weight and harvest index in all lines by 25%, 21%, 19%, 13% and 4% compared to the irrigation condition, respectively. Based on the positive and significant correlation of grain yield performance under the irrigation conditions against the rainfed conditions (r= +0.782**), high yield potential can be an important factor in selecting drought tolerant cultivars, but this factor alone is not enough and due to its correlation with the growth indices, the latter can be used in this regard. LAR and SLA indices showed a positive and significant correlation with grain yield under the irrigation condition and at the sensitive developmental stages including heading (r=+0.663* and r=+0.608*) and 10 days after anthesis (r=+0.704* and r=+0.673*). Under the rainfed condition, a positive and significant relationship (r=+0.647*) was observed between LAR and grain yield in the last stage of sampling. There was a positive and significant relationship between RGR and NAR, biological yield and straw yield. RGR also showed a positive and significant relation with LWR (r=+0.640*) in the second stage of sampling. Among the components of RGR, NAR was the main and effective factor, which had a negative and non-significant correlation with LAR, so that the lines with higher LAR had lower NAR and therefore lower RGR. There was a positive and significant relationship between LAR components such as LWR and SLA with LAR. In general, among the RGR components (LAR and NAR), it can be said that the LAR index and among the LAR components (LWR and SLA), the SLA index, while having a positive and significant relationship with grain yield at the sensitive developmental stages, are considered as effective factors in grain yield. Consequently, it seems that these two parameters can be identified as important growth indicators related to grain yield.
