تاثير تغذيه برگي سولفات روي بر الگوي رشد ريشه چهار رقم گندم در سطوح مختلف رطوبت خاك

چكيده انگليسي :

Effects of ZnSO4 Foliar Application on the Root Growth Pattern of Four Wheat Cultivars Under Different Levels of Soil Moisture Sayed Mohammad Javad Ahmadi Email address Mj Ahmadi@ag iut ac ir September 14 2014 Department of Agronomy and Plant Breeding Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Hamid Reza Eshghizadeh and Morteza Zahedi Supervisor hr eshghizadeh@cc iut ac ir mzahedi@cc iut ac ir Abstract Wheat as a main crop plays a significant role in supplying food and human health However water stress and zinc deficiency are important factors limiting the growth and yield of crop plants including wheat On the other hand roots are important not only for providing water nutrients and hormones but also for their contribution to water stress tolerance and nutrient use efficiency Therefore this study was conducted in order to investigate the roles of root morphological characteristics and also foliar application of zinc sulphate on the responses of wheat cultivars to water deficit In this experiment four wheat cultivars Ghods Roshan Chamran and Kavir were evaluated under four levels of irrigation irrigation based on 100 90 75 and 50 of crop water requirement and two levels of zinc foliar application of zinc sulphate at stem elongation stage and non sprayed as control The experiment was carried out at Isfahan University of technology arranged as factorial in a completely randomized design with three replications Wheat plants were harvested at physiological maturity Measured traits were SPAD index plant height tiller numbers spike numbers grain weight per plant and shoot dry weight and also root parameters including root dry weight volume cumulative surface and length and diameter determined at 0 30 30 60 and 60 100 cm soil depths The results showed that there were significant differences among cultivars for all measured traits except plant height and SPAD index Tiller numbers spike numbers grain weight per plant and shoot dry weight were decreased as the available water was reduced in soil However the responses of plant height and SPAD index to water deficit were dependent on cultivar irrigation and zinc level Root dry weight was decreased under mild and severe levels of water deficit it was instead increased with zinc foliar application under mild water deficit in cultivars Ghods and Roshan and under severe water deficit in Ghods The extent of decreases in root dry weight was greater for the roots measured at 30 60 cm soil depth The responses of other root parameters including root volume cumulative root surface and length and root diameter to water stress were dependent on both experimental treatments and the soil depth at which roots were measured The root system of Ghods and Chamran cultivars showed more flexibility in response to water deficit as compared to those of Kavir and Roshan Foliar spray of zinc sulphate in average increased grain yield grain weight per plant 12 3 percent However the extent of the increases was higher under irrigation based on 100 24 6 percent than under irrigation based on 90 75 and 55 3 75 10 79 and 8 33 percent respectively of crop water requirement The increase in grain yield was significant only in Ghods 28 6 showing that this cultivar was more responsive to zinc application than others The effects of foliar application of zinc sulphate on cumulative root surface and length were more evident in roots measured at 0 30 cm and on root dry weight and root volume at 30 60 cm soil depth Root depth was not significantly affected by zinc application Chamran was the most responsive cultivar in most cases positively in terms of the changes in root parameters under zinc foliar application instead zinc application generally restrained root growth of Ghods Roshan and Kavir Under all irrigation levels and in most cases there were significant negative correlations between grain yield and the changes in root characteristics At soil depth of 0 30 cm the negative corr

احمدي، محمد جواد

تاثير تغذيه برگي سولفات روي بر الگوي رشد ريشه چهار رقم گندم در سطوح مختلف رطوبت خاك

تنوع ژنتيكي , تنش كمبود رطوبت , سطح تجمعي ريشه , لايه هاي خاك , محلول پاشي