Abstract
Cowpea (Vigna unguiculata [L.] Walp.) is important food legume of sub-tropic to tropic area, well adapted to hot and dry environment. However, reproductive processes and pot yield of cowpea are severely affected by high night temperature. Under the heat stress, importance of proline accumulation in reproductive organ for high yield of cowpea has been suggested. For the analysis of proline accumulation in pollen under the high temperature, genotypic differences of cowpea in heat-tolerance were investigated.
One day before anthesis, both heat-tolerant and heat-sensitive genotype reduce proline concentration in anther at heat-stressed condition. Heat-tolerant genotypes CB27 and TVu4552 kept almost same concentration of proline in pollen at normal and heat-stressed condition. However, heat-sensitive genotype CB5 could accumulate lower concentration of proline in pollen at heat-stressed condition. Retentivity of pollen proline concentration at stressed condition could be an important factor of heat-sensitivity of cowpea genotype.
