Evaluation of some Bread Wheat Genotypes under Saline Soil Conditions Using Tolerance Indices and Multivariate Analysis

Abstract

The present investigation was conducted in a field experiments at Sakha Agricultural Research Station Farm to evaluate 24 bread wheat genotypes during the two growing seasons 2014/2015 and 2015/2016 under normal and salinity stress conditions. The experimental design used was a randomized complete block design with three replicates. Eleven stress tolerance indices (STI's) were calculated based on average grain yield under normal and stress conditions across the two seasons. Moreover, cluster analysis was performed to identify the similarity/dissimilarity among the tested genotypes for grain yield and salinity tolerance. Results showed large values of broad-sense heritability (h b 2) coupled with high values of genetic advance as a percent of mean (GA%) at 5% selection intensity for number of spikes/m 2 and number of grains/spike in the adequate site. Concerning the salt stressed soil, the grain yield ratio, number of spikes/m 2 and grain yield recorded the highest values of h b 2 and GA%. However, there were crucial differences among tested genotypes in respect to grain yield under non-stress and salt stress sites, which demonstrates high genetic diversity among them that enabled us to screen salt tolerant genotypes. Already, the tested wheat genotypes exhibited different responses for salinity stress tolerance indices (STI's). Perfect and positive correlation coefficients (r = 1) were found between three pairs of indices (STI and GMP), (SSPI and TOL) and (CV and SSI) where each one of the previous three pairs occupied one dot on the biplot graph indicating that the three indices are identical for ranking genotypes for salinity tolerance and they could be interchangeably used as a substitute for each other. Therefore, using these pairs of (STI's) together in the same study is considered a waste of time and effort. The cluster analysis classified the tested genotypes into five main groups (clusters) where each group contained the genotypes that showed similar yield potential and salinity tolerance. The fifth cluster contained two promising genotypes namely; lines 2 and 17 that were characterized by moderate grain yield in each of the normal and salt soils recording the lowest grain yield reduction. Also, they occupied the first and second ranks among the tolerant genotypes for salinity stress. Accordingly, results would give a good chance to achieve genotypic improvement of wheat through the hybridization among genotypes taken from different clusters.

Salinity Stress Affects Field Performance of Wheat Genotypes Differing in Genetic Background

“…As indicated in (table 2), variations in rainfall quantity and distribution between the two seasons caused a differential response of genotypes to salinity levels. Similar findings were reported by Dhayal & Sastry (2003); El-Hendawy et al (2005); Darwish et al (2017) and Gadallah et al (2017). Salinity levels effect: Means presented in (table 5) revealed that days to maturity and grain filling period increased significantly at moderate salinity compared to the control.…”

Evaluation of some Bread Wheat Genotypes under Normal and Saline Soil Conditions

“…Data indicated that Misr1 and Line 2 can be used in both normal and saline soil conditions. These results are in agreement with Darwish et al, 2017 andGadallah et al, 2017. Interaction effects A-Effect of years: Table (6) illustrates the average values of all studied characters combined across the two normal and saline soil conditions in the two seasons.…”

“…For grain yield reduction % the lowest values were recorded for Line 11, 14 and 2 (38.89, 41.54 and 44.81%), respectively. Similar finding were reported by Darwish et al (2017) and Yassin et al (2019). Tables 8 & 9 showed the interaction among saline soil conditions, seasons and genotypes for all studied characters.…”

“…However, the three indicators MP, HM and MSTI gave a different arrangement of genotypes to carry them to salinity. A similar trend of results was found by Ali and El-Sadek (2016), Darwish et al, (2017) and Yassin et al, (2019).…”

Evaluation of Bread Wheat Advanced Lines Under Salinity Conditions Using Tolerance Indices

“…Finally, Group D consisted of three genotypes G12, G8 and G5 that displayed the lowest values and subsequently these genotypes could be considered the highly sensitive ones. These results were in consistence with those of Bagci et al (2007), Ahmadi et al (2012), Asadi et al (2012), Badran andMoustafa (2014), Abd El-Mohsen et al (2015); Desheva and Kyosov (2015), Sanjay et al (2015), Sara et al (2015), Afiah et al (2016), Darwish et al (2017), Maha et al (2017), Yassin, et al (2019 and Gadimaliyeva et al (2020). Yp is grain yield under 6000 ppm, Ys is grain yield under 9000 ppm, SSI is stress sensitivity index, MP is mean productivity, GMP is geometric mean productivity, STI is stress tolerance index, YI is yield index and YSI is yield stability index.…”