Genetic Control of High Temperature Tolerance in Wheat as Measured by Membrane Thermal Stability

Heat stress is an important production constraint of wheat (Triticum aestivum L.) affecting many plant biological activities in the cell membrane. This study determined the genetic control of heat tolerance through diallel analysis of selected wheat germplasm. Heat-induced damage of plant membranes was assayed by the membrane thermal stability (MTS) assay, which measures electrolyte leakage from leaf tissue after exposure to high temperature. Six wheat genotypes ('TAM 107', 'TAM 108', 'Arlin',' Kauz', 'Glennson 82', and 'Siete Cerros') were hybridized in a complete diallel, and MTS was measured on 12 d old F1seedlings. The mean square for general combining ability (GCA) was four times that of specific combining ability (SCA), indicating the importance of additive gene effects in acquired thermal tolerance. Maternal effects accounted for 67% of reciprocal variation, suggesting that maternal seed-source effects may be important in hybrid seed. These results suggest that heat tolerance based on MTS can be improved using the existing genetic variability available within the germplasm evaluated in this study.

Genetic Control of High Temperature Tolerance in Wheat as Measured by Membrane Thermal Stability Academic Article