Response Selection for Drought Toleranc in Maize

Abstract

The present study was carried out in 4 seasons during 4 years from 2017 to 2020 at the field of BeniSuef in. Res. Sta., Middle Egypt com. The main objectives were to develop new maize populations of increased tolerance to drought and evaluate predicted and actual gains from one cycle of S 1 recurrent selection. Two sets of 121 S 2 's were developed from the local population Pop 277, the 1 st set was evaluated under well water (WW) and intermediate water-stress (IWS) conditions. The highest yielding 18 lines (15%) were selected under each environment. Intercrossing of the two groups of 18 S 1 's was done in separate blocks. The resulted of new 2 populations, Pop277-IWS and Pop277-WW) indicated wide genetic variation among S 1 progenies for most studied traits under all selection environments. Broad sense heritability estimates were generally higher under water-stress than under non-stress conditions. Results indicated that anthesis -silking interval, ears plant -1 and stay green traits could be valuable criteria in increasing the selection efficiency for drought tolerance. Actual superiority in grain yield over Pop277 due to one cycle of S 1 recurrent selection was (26.77%) by the improved populations (Pop277-IWS),