Abstract
Cowpea (Vigna unguiculata [L.] Walp.) is used as important sources of proteins and carbohydrates in the tropics and subtropics because it is well adapted to hot and dry environment. But the grain yield of cowpea is severely inhibited by high night temperature.
We reported last year that retentivity of pollen proline concentration at stressed condition could be an important factor of heat-sensitivity of cowpea genotype. In the present study, we have undertaken gene expression analysis of proline transporters, VuProT1 and Vu ProT2 by RT-PCR.
Both ProT1 and ProT2 gene expression were observed in all organs we analyzed. Expression of ProT2 was almost equal level in all organs. However, ProT1 was abundantly-expressed in anthers and flower stalks. It seems ProT1 play important roles for transport proline into flower organs. ProT1 was expressed more in anthers of heat-tolerant line TVu4552 than heat-susceptible lines CB5 and Bambey23 in heat-stressed condition.
