نوع مقاله : پژوهشی
نویسندگان
1 کارشناسی ارشد ژنتیک و به نژادی گیاهی دانشگاه علوم کشاورزی و منابع طبیعی ساری
2 گروه اصلاح نباتات، دانشکده علوم زراعی، دانشگاه علوم کشاورزی و منابع طبیعی ساری
3 گروه اصلاح نباتات، دانشکده علوم زراعی ، دانشگاه علوم کشاورزی و منابع طبیعی ساری
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objective: Rice is a strategic crop and one of the most important food sources in most countries, including Iran. Drought stress causes the most damage to the plant among all existing stresses, and since rice has the highest potential for crop production under flooded conditions, drought is considered a very serious threat to its production. Drought threatens large areas of rice cultivation. Given the increasing population and the shortage of water resources, improving drought stress tolerant genotypes is a necessity. The requirement for identifying drought stress tolerant genotypes is to examine changes in morphological traits under stress conditions. The aim of this study is to identify drought-tolerant genotype(s) by evaluating morphological traits under different irrigation periods.
Materials and Methods: In this study, 25 different rice genotypes were used to identify drought-tolerant genotype(s) based on morphological traits, along with a drought-tolerant control Kinanadang patong (KP) and a drought-sensitive IR64 under field conditions. This experiment was conducted in split plots based on a randomized complete block design with 3 replications. To investigate drought stress tolerance, morphological traits including number of days to 50% flowering, plant height, number of fertile tillers per plant, spike length, number of full grains per panicle, number of hollow seeds grains per panicle, 100-grain weight, paddy width, paddy length and Rice paddy yield were used. Cluster analysis was used to group and identify superior genotype(s).
Results: Analysis variance of the data showed that there was a significant difference in drought tolerance between the studied genotypes. The results of this study showed that number of fertile tillers per plant and number of full grains per panicle are important yield components and a suitable indicator for selecting drought-tolerant genotypes. With increasing irrigation periods, the traits of plant height, number of tillers per plant, number of full grains per panicle, 100-grain weight and plant yield showed a decreasing trend. In examining the average of the studied traits in different irrigation periods, 7 genotypes showed their superiority in terms of the traits of number of fertile tillers per plant and number of full grains per panicle and plant yield. Also, in cluster analysis, some of these genotypes were placed in a group that showed higher plant yield than other groups in all irrigation periods.
Conclusion: As a result, the selected genotypes, having high yield in different irrigation periods and being in the superior groups in terms of yield in all irrigation periods, have been identified as promising lines with drought tolerance that can be used in future rice breeding programs.
کلیدواژهها [English]
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