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 (h 2 b ) 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 h 2 b and high GA estimates. The best ARRB, 35(2): 25-40, 2020; Article no.ARRB.55937 26 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. Original Research Article

Thirty-nine genotypes of bread wheat (Triticum aestivum L.) collected from different regions in Egypt and two commercial varieties were used in this study, to estimate the tolerance indices and to establish the drought tolerance in 41 genotypes. Significant genotypes mean squares were detected for all studied traits, except number of spikes per m 2 and grain per spike under water stress. Using stress susceptibility index (SSI), genotypes 4, 6, 1, 31, 19, and 24 were classified as highly drought tolerant. According to stress tolerance index (STI), twelve genotypes were the top performer under stressed conditions. Twenty-nine genotypes showed lowest STI values (< 0.10) which implies that these genotypes were highly susceptible to drought. The greater values of yield stability index (YSI) were observed in genotypes 8,39,17,22,28,12,26 and 37. Based on sensitivity drought index (SDI) the six genotypes 4,6,1,31,19 and 24 revealed the highest values and were identified as tolerant under stress conditions. According to drought index (DI). Grain yield under stressed conditions (YS) was significantly and positively correlated with STI and DI. Yield in non-stress condition (YP) was significantly and positively correlated with YS, SSI, STI, SDI, and DI and negatively correlated with YSI. The total variation expressed between the two components was 99.70%. The variable that has the highest PCA1 value and the lowest PC2 was found excellent in screening genotypes under stress and non-stress conditions. Also, genotypes 17 and 37 are the most tolerant genotypes under water stress.

To increase the genetic progress in wheat (Triticum aestivum L.) yield, breeders search for germplasm of high genetic diversity, one of them is the landraces. The present study aimed at evaluating genetic diversity of 20 Egyptian wheat landraces and two cultivars using microsatellite markers (SSRs). Ten SSR markers amplified a total of 27 alleles in the set of 22 wheat accessions, of which 23 alleles (85.2%) were polymorphic. The majority of the markers showed high polymorphism information content (PIC) values (0.67-0.94), indicating the diverse nature of the wheat accessions and/or highly informative SSR markers used in this study. The genotyping data of the SSR markers were used to assess genetic variation in the wheat accessions by dendrogram. The highest genetic distance was found between G21 (Sakha 64; an Egyptian cultivar) and the landrace accession No. 9120 (G11). These two genotypes could be used as parents in a hybridization program followed by selection in the segregating generations, to identify some transgressive segregates of higher grain yield than both parents. The clustering assigned the wheat genotypes into four groups based on SSR markers. The results showed that the studied SSR markers, provided sufficient polymorphism and reproducible fingerprinting profiles for evaluating genetic diversity of wheat landraces. The analyzed wheat landraces showed a good level of genetic diversity at the molecular level. Molecular variation evaluated in this study of wheat landraces can be useful in traditional and molecular breeding programs.

Website: http://strategy-plan.asu.edu.eg/AUJASCI/ ASSESSMENT OF SOME AGRO-MORPHOLOGICAL TRAITS IN GENOTYPES OF EGYPTIAN FABA BEAN (VICIA FABA L.).