Selection Criteria and Selection Environment for Drought Tolerance of Egyptian Wheat (Triticum aestivum L.) Landraces
Ahmed Medhat Mohamed Al-Naggar *
Department of Agronomy, Faculty of Agriculture, Cairo University, Giza, Egypt.
Mohamed Abd El-Maboud Abd El-Shafi
Department of Agronomy, Faculty of Agriculture, Cairo University, Giza, Egypt.
Mohamed Helmy El-Shal
National Gene Bank, Agricultural Research Centre, Giza, Egypt.
Ali Hassan Anany
National Gene Bank, Agricultural Research Centre, Giza, Egypt.
*Author to whom correspondence should be addressed.
Abstract
Strong correlations between wheat traits and drought tolerance (DT) associated with high heritability and high genetic advance from selection would allow plant breeder to use such traits as selection criteria. The objective of the present investigation was to determine the optimum selection criteria and selection environment for drought tolerance via estimation of correlation coefficients (r) among 13 agronomic, grain yield and quality traits and DT of 20 wheat landraces, broad-sense heritability (h2b) and genetic advance (GA) from selection for such traits under well-watered (WW) and water stressed (WS) environments. A two-year experiment was carried out using a split-plot design with four replications. Results concluded that the best selection criterion for drought tolerance in our study was grain yield/plant (GYPP), followed by a number of grains/spike (GPS), grain filling period (GFP), grain starch (GSC) and protein (GPC) content, plant height (PH) and days to maturity (DTM), since they showed high (r), high h2b and high GA estimates. The best selection environment was WW for days to anthesis, PH, spikes/plant, GPS, spikelets/spike, GYPP, GPC and WS for DTM, GFP, GSC and thousand-grain weight traits. This information could help future breeding programs in selection for improving drought tolerance of wheat.
Keywords: Deficit irrigation, trait correlations, heritability, genetic advance, genetic variability.