| Summary: | 碩士 === 國立臺灣大學 === 植物科學研究所 === 94 === Impairment of tomato pollen during anther development by elevated temperature contributes to decreased fruit set. In this study, I found that continuous exposure of tomato to high temperatures (day/ night temperature of 35/ 30 and 30/ 25 °C) decreased pollen activity and reduced of pollen grain germination. To isolate these heat-induced genes affecting pollen viability, suppression subtractive hybridization was used to isolate cDNA fragments from heat-tolerant tomato anther. In these heat-induced genes, sucrose synthase (SUS3) and S-adenosyl-methionine synthetase (SAM3), were chosen for further study. Real-time PCR confirmed that these two genes, SUS3 and SAM3, were induced by high temperature in the heat-tolerant tomato. Furthermore, transgenic tomato expressing SUS3 or SAM3 was used to verify the functions of these genes in protecting tomato from heat. Transgenic plants were produced by Agrobacterium tumefaciens with pCAMBIA-1390AP, which contains sweet pepper ferredoxin-like protein, and Erwinia carotovora was used as the selection agent. Transgenic tomato L4783 containing the 35S::SAM3 shows higher pollen viability and pollen tube germination rate than wild-type L4783 does. These results may point out that tomato with over-expression of SAM3 may allow tomato to increase its fruit set in tropical weather.
|
|---|
