番茄在逆温下单性结实品种的结果性能及遗传研究

THE NATUKAL FRUIT SETTING CHARACTER UNDER UNFAVOURABLE TEMPERATURES AND INHERITANCE OF PARTHENOCARPY IN TOMATO PLANTS

选用在逆温条件下单性结实的品种ＯＳ和非单性结实品种早粉２号及矮秆２０１等为试材，观察比较它们在高、低逆温条件下的开花结果动态和花粉的育性。结果表明，在春季日最低气温６．１～１５．０℃期间，ＯＳ所开花朵９１％座果，而早粉２号和矮秆２０１则分别仅有３９．５％和２１．８％座果；在早秋日最低气温高达２５～２２℃时，ＯＳ开花座果率在４０．７％－１００％之间，而早粉２号和矮秆２０１则分别仅有０％～５％和０％～８％。两类品种间差异显著，表明在逆温条件下单性结实品种ＯＳ有比较稳定的结果性能。经测定，两类品种的花粉育性并无显著差异，在适温条件下，均能正常受精结籽，进行有性繁殖。由此认为，在逆温下单性结实品种可用作选育新一代耐高、低温优良品种的重要种质资源。通过上述两类品种之间的杂交、回交等６个世代的系统观测，认为在逆温下单性结实性状的遗传，受一对隐性基因控制。

The tomato line OS with heritable tendency for parthenocarpic fruit set in high and lownight temperatures,and 2 normal, seeded cultivars of Zaofen No.2 and Determinant 201 were studied fornatural fruit setting and inheritance of parthenocarpy.The result showed that, during spring period, lownight temperature ranged between 6.1 to 15℃,the fruit setting of OS reached 91 percent, while ZaofenNo.2 and Determinant 201 were only 39.5 and 21.8 percent respectively; during early autum period,highnight temperatures ranged between 25 to 22℃, OS fruit setting percent ranged from 40.7 to 100,whilezaofen No.2 and Determinant 201 were only 0 to 5 and 0 to 8 respectively.The fruit setting of two types asmention above were singificant difference, indicating that the parthenocarpic line OS has more stableheritable tendeney for fruit setting under unfavourable temperatures than the others. After determining the pollen germination percent at low temperature, there were no difference between two types.They all canset seeded fruits and do sexual reproducation at zone of optimum temperatures.So author consider thatthce parthenocarpic tomato lines would be important germplasm in breeding superior new cultivars for tol-erance to high and low temperatures. The inheritance of parthenocarpy were studied in the field in crossesbetween lines OS and 83- 15 (parthenocarpy) with Zaofen No. 2 and Determinant 201(non-parthenocarpy).F_1 and backcross (with non-parthenocarpic parents) data indicated that theparthenocarpic inheritable tendeney in lines OS and 83-15 is recessive, F_2 data fit a 3 seeded: 1 seedlessratio, backcross (with parthenocarpic parents)data fit a 1 seeded: 1 seedless ratio,indicating thatparthenocarpy in the material of lines OS and 83-15 under low night temperature condition,are controlled by a single recessive gene.