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Tainan-White（TNW）is a native maize population which has been cultivated for over 80 years in Taiwan. TNW has been conventionally ultilized as a green corn. Eight Tainan-White maize populations collected from Pingtung, Kaohsiung, Tainan, Yunlin, Taichung, Taipei, Hualien and Taitung areas were planted at Taichung, and then, we took the seeds（8 populations）as material to investigate the germination characters of seeds at constant temperature between 5℃ and 40℃ in growth chamber. The results showed that days to first germination, period of effective germination, germination rate, mean germination time and germination coefficient were significantly different among populations, temperature and interactions between them, thus variation type among populations under different temperature differ. The germination characters of Taipei population were worse than other populations at almost all temperatures. At 5℃~25℃, the germination characters of Hualien population were better than other populations, when temperature raised above 25℃, populations of Taichung, Yunlin, Pingtung and Taitung germinated better. The correlations among germination characters were different among eight populations. And regression analysis of stability of germination traits between populations under different temperatures showed that, the parameters of stability in germination traits were significantly different between populations. The results indicate that Tainan-White maize populations were differentiated into ecotype in different areas by germination traits.
Results of regression equation of temperature on mean germination rate of eight populations showed that the minimum temperature of germination was in a range of 2.9℃~3.5℃, and the thermal time of germination was in a range of 55.1℃d~59.0℃d. The optimum temperature of Pingtung, Tainan, Yunlin, Taichung, Hualien and Taitung populations was 25~30℃, and the optimum temperature of Kaohsiung and Taipei populations was 30℃. The maximum temperature for germination of eight populations was 40~45℃.
Eight S4-selected inbred lines from the population cultivated at Taichung（A）、Tainan（B）、Yunlin（C）、Taoyuan（D）、Taitung（E）、Changhua（F）、Pingtung（G）and Hualien（H）county in Taiwan were used in this study. The inbred lines were crossed following a diallel mating design producing 56 F1. The inheritance of germination characters of Tainan-White maize were studied with 8×8 diallel crosses. Results are summarized as follows：Additive and dominant effects were highly significant in all germination characters, with the additive effect being more important than the dominant effect in the diallel analysis. Mean degrees of dominance on all germination characters were partial dominance. Germination rate was found to be mainly controlled by the polygenes. There are at least three gene pairs determing the mean germination time, and at least two gene pairs determing germination coefficient and germination speed. Heritability in narrow sense of germination rate, germination coefficient and germination speed was higher than 80%, but that of mean germination time was 62%.
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