| Summary: | 碩士 === 國立屏東科技大學 === 熱帶農業暨國際合作研究所 === 91 === Under different temperature regime (30/25℃, 28/20℃, 25/18℃, 20/18℃, 20/12℃; day/night), gene-cytoplasmic male sterility ‘Acc. 195’ plants had greater vegetative growth than that of its normal maintainer lines. Except for the carotenoid contain, plant height, internode length, leaf area, and chlorophyll contain except for the carotenoid contain in the CMS plant were significantly larger than the normal plant. ‘Acc. 14’ and ‘Acc. 17’ plants under 28/20℃ day/night treatment showed abundant growth than their own normal isogenic maintainer. However, under 25/18℃ day/night temperature regime ‘Acc. 17’ plant could set fruits and its anther could produce normal viable pollen grains with numbers showed no significant difference to those of normal maintainer line. There was also no significant difference in plant growth character between the recovered ‘Acc. 17’ plants and its normal maintainer plants.
‘Acc. 17’ plants treated seedling established in summer and treated with 25/18℃ day/night temperature regime at anthesis of the first branch, the recovering fertility temperature regime only react on branch with non-visible bud and make the original male sterile plant fertile. According to cytological microsporogenesis observation recovering temperature regime must be present in archesporial cell stage or the earlier primordial stamen differentiation stage. When under 28/20℃, anther showed the degeneration delaying and vacuolate tapetum encroaching on the tetrad caused the collapes of developing microspores. While in that under 25/18℃, tapetum developed normally and the microspores could release from tetrad to form normal pollen grains.
Analysis on the expression of male fertility in different ‘Acc. 17’ generations indicated that: The expression of male sterility of F1 generation and BC1F1 generation were unstable and related to the air temperature regime about twenty days before the anthesis of pepper flower. Cool air temperature regime (25/18℃) increased the expression of male fertility; while hot air temperature regime (28/20℃) caused plants to be sterile. Nevertheless, ‘Acc. 17’ F2 generation showed segregation of total male fertile, total male sterile and unstable male sterile (fertile) plants which fit χ2 ratio of 9：3：4. It assumed that the genetic control of the unstable sterility (fertility) was by two major epistasis recessive genes.
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