Evaluation of Some Morphological and Agronomical Traits of Rapeseed Cultivars in Response to Withhold Irrigation from Different Growth Stages

摘要

Water deficit is an important factor limiting crop production worldwide. Drought stress can be managedby improving the availability of soil moisture conserved and selecting drought tolerant genotypes. In order toevaluate water deficit effects on morphological and agronomical traits in rapeseed cultivars, an experiment wasconducted at research farm of the Seed and Plant Improvement Institute, Karaj, Iran (35°59′N, 50°75E and 151m altitude) over two successive years (2007-2009). The experiments were arranged in a split-plot on basis ofrandomized completely block design (RCBD) (water limitation treatments as a main plots and cultivars as asub-plot) with three replications. The result of this experiment showed that rapeseed cultivars and water stresssignificantly affected on all traits except oil content, 1000-seed weight and harvest index. The least reductionof seed yield in water deficit conditions has produced in Zarfam cultivar. Also, this cultivar had lowerdecreasing of oil yield in stress conditions and it has the best adaptation in water deficit conditions. Theseresults may be due to the reduction of photosynthesis and chlorophyll content.