pp. 40-50 | DOI: 10.29329/ijiaar.2017.100.5 | MID: MANU-1711-30-0004
Published Online: December 19, 2017
Manuscript Views: 89 | Manuscript Download: 68
Pollen viability represents sporo-gametophytic tolerance to the heat stress. Therefore, pollen fertility index under heat stress can be exploited to differentiate resistant and susceptible genotypes. Information relative to genetics of pollen viability is necessary to improve pollen viability under heat stress. Studies were initiated to develop and evaluate heat tolerant populations under controlled and field conditions. Result showed that pollen fertility index of genotypes was stable over the years. It showed moderate to high heritability, which was due to greater magnitude of genotypic effects in total phenotype. Studies showed that pollen fertility was primarily controlled by dominant type of genetic variability which showed that selection per se for the pollen fertility could be improved through recurrent selection. General combining analysis showed that gametophytic type of heat resistance was important in the inheritance of pollen viability. Heat resistance was dependent on the genotype of gametes as indicated from lack of relationship between mean performance of inbred line per se and their progenies for pollen viability.
Keywords: Heat stress, reproductive fitness, pollen staining, floral head, sterility, abiotic stress, mobilization of reserve, gene action, dominance