AGRONOMIC AND PHYSIOLOGICAL STUDIES ON SOME EXOTIC AND LOCAL BREAD WHEAT GENOTYPES UNDER SALINE SOIL CONDITIONS IN NORTH DELTA REGION

Soil salinity is the major global limitation to wheat production. Thus, ten bread wheat exotic lines and local cultivars were studied under normal and moderate saline soil conditions during 2017/18 and 2018/19 growing seasons. the objective was to understand the effects of salinity stress on some agronomic and physiological characters and to estimate some selection indices for salt tolerance in wheat. The studied characters were plant height and grain yield and its components in addition to relative water content, contents of chlorophyll a and b, proline and malondialdehyde and catalase activity in the flag leaves. The two seasons and saline conditions behaved differently. Besides, sufficient genetic variability among the studied genotypes was detected. Moreover, the variance due to saline conditions was the most important comparing to the other sources. Most of studied characters were higher in their mean values in the second season than the first one. All mean values of the studied characters decreased under the saline conditions, except for proline and malondialdehyde contents and catalase activity. Genotypic main effect plus genotype by environment interaction (GGE) Biplot analysis revealed that Line 2, Sakha 95, Misr 3 and Sids 14 had high yielding ability and relative tolerance under salinity conditions. Based on correlation coefficients, the high values of relative water content, chlorophyll, proline contents and catalase activity in addition to the low value of malondialdehyde content may be used as physiological selection criteria for salt tolerance screening of wheat genotypes