نوع مقاله : مقاله پژوهشی
نویسندگان
1 بخش تحقیقات زراعی و باغی، مرکز تحقیقات کشاورزی و منابع طبیعی استان خراسان رضوی، سازمان تحقیقات، آموزش و ترویج کشاورزی، مشهد، ایران، 2و3 استاد دانشکده کشاورزی دانشگاه فردوسی مشهد، گروه زراعت و اصلاح نباتات،
2 استاد دانشکده کشاورزی دانشگاه فردوسی مشهد، گروه زراعت و اصلاح نباتات،
3 استادیار بخش تحقیقات زراعی و باغی، مرکز تحقیقات کشاورزی و منابع طبیعی استان خراسان رضوی، سازمان تحقیقات، آموزش و ترویج کشاورزی، مشهد، ایران.
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Evaluation of physiological reactions in different cotton cultivars under drought stress, is a precise and confident method for monitoring of plant and water relations and it can be applied to breeding of tolerant cotton cultivars. Therefore, this study was carried out for evaluation of stomatal control, leaf and canopy temperature and also maximum efficiency of photosystem II (ΔF/F́m). Field experiment was carried out using two cotton drought tolerant cultivars (Armaghan and Varamin) and two cotton drought sensitive (Coker349 and Nazili84) as sub plots at three levels of water application [33% (I33%), 66% (I66%) and 100% (I100% of water requirement) as main plot using split plot based on complete block design with three replications at Agricultural Research Station of Kashmar in 2011. Results showed drought stress significantly increased (33.3%) stomatal resistance, in addition to its value were 22% more in tolerant cultivars compared with sensitive cultivars. Also drought stress significantly increased leaf temperature (15.3%) and decreased maximum efficiency of photosystem II (ΔF/F́m) (14.8%). But these variations were different in sensitive and tolerant cultivars. With increasing intensity of drought stress, tolerant cultivars showed more increasing of stomatal resistance compared with sensitive cultivars. Variations slope of leaf temperature with increasing in stomatal were more in sensitive compare with tolerant cultivars. The results showed significant difference between maximum efficiency of photosystem II in cotton cultivars. The highest and the lowest of maximum efficiency of photosystem II belonged to Varamin as tolerant cultivar and Coker349 as sensitive cultivar in respectively.
کلیدواژهها [English]