Combining ability for some agronomic characters in grain sorghum under saline conditions and biochemical genetic markers for salinity tolerant genotypes [electronic resource].

Includes references.

Twenty-four hybrids and their parents of grain sorghum were evaluated under normal and saline soils at Nubaria Agric. Res. Stat. in 2003 and 2004 growing seasons. The genetic analysis was conducted using line x tester analysis. Significant differences were found among years, genotypes, salinity treatments, parents and their F1's for all studied traits. Analysis of variance of salinity sensitivity index (SI) exhibited significant differences among crosses, parents, crosses vs parents and for male and female effect... indicating the important role of some heterotic effect in sorghum for salinity tolerance. Regarding Sl, the most salinity tolerant parents were (ICSR89025) m2 and (ICSR90015) m" (0.74 and 0.65, respectively) among males and f3 (ICSA-37),f6 (ATX631) and 12 (ICSA-14) (0.39, 0.60 and 0.61,respectively) among females. Based on both yield under saline conditions and S1, there were four promising hybrids viz H3 (ICSA-1 x ICSR 89038), H7 (ICSA-14 x ICSR 89038), H14 (ICSA70 x ICSR 89025), and H24 (ATX631x ICSR 90015), where SI were 0.44, 0.54, 0.09 and 0.48, respectively. Estimates of general combining ability effects showed that ICSA14, ICSA 37, ICSR 89025 and ICSR 90015 were the best general combiners for yield and salinity tolerance and the hybrids Hs, H7, H14 and H2" were the best regarding SCA effects for SI while H1 had significantly positive SCA effect for grain yield. Results indicated that both additive and non-additive gene effect were important to improve grain yield of sorghum grown under saline conditions. The tolerant parents were distinguished with five common bands which were not found at the sensitive genotypes at MW 255.81,188.62,162.62,43.78 and 32.12 KDa, except the female f6 which lacked two bands at MW 255.81 and 188.62 KDa. Most of these common bands were present in the most tolerant hybrids. Generally, the electrophoretic patterns of water soluble protein could be a useful tool for the identification and characterization of the tolerant grain sorghum genotypes for salt stress conditions.

Summary in Arabic.

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