Phenotypic variation in waterlogging stress tolerance among wheat cultivars and its wild relatives

摘要

Waterlogging is one of the limiting factors affecting global wheat yield including Pakistan. Its harmful effects on wheat crop depend on growth stage and type of cultivars. The main objectives of this study were to screen different wheat cultivars/accessions against waterlogging stress at imbibition stage and then at two leaf stage for those cultivars exhibiting tolerance at imbibition stage. In total one hundred and nineteen wheat cultivars/accessions were screened at imbibition/germination. These 119 cultivars/accessions were grown in Indian subcontinent during different time periods from early 20 th century till present. Seeds after sowing were immediately exposed to waterlogging stress for 8 days. None of the cultivar/accession showed germination during eight days of stress. Waterlogging stress was terminated and kept for revival for one week under normal conditions. Sixteen cultivars/accessions showed revival (germination) in one week time. These 16 cultivars/accessions, along with three randomly selected cultivars, were further screened at two leaf stage against waterlogging stress for 16 days. These cultivars/accessions responded differently against waterlogging stress. Phenotypic traits like shoot length, shoot mass and root mass were recorded. Seven cultivars/accessions (010780, 010786, LYP-73, Lasani-2008, Punjab-76, Punjab-85 and Shakar-95) did not show significant changes in root mass, shoot mass and plant height under waterlogging stress and were considered tolerant at two leaf stage. This study helped use to find cultivars which showed tolerance at germination and two leaf stage against waterlogging stress.