| Field experiment with potato Kexin-13 as material was conducted, and spraying of three chemical regulators, 2-N, N-diethylamino ethylcaproate (DTA-6), mepiquat chloride (DPC) and uniconazole (S3307) were performed. The results showed that PGRs significantly increased per tuber weight, starch yield and fresh yield. Among them, DTA-6 treatment showed positive effect, with the weight of tuber, the yield of starch, the yield of fresh potato and the content of starch increased by 10.40%, 40.26%, 26.56% and 11.32%, respectively, whereas the content of reducing sugar reduced by 20%. In addition, PGRs enhanced chlorophyll content, net photosynthetic rate, transpiration rate and intercellular CO2 concentration, thus having higher photosynthetic activity. Photosynthetic index was positively correlated with yield. The starch and sucrose content showed downward and upward trend, and the amylase activity decreasing trend. The invertase activity showed different pattern. Our findings indicated that PGRs increased yield and improved quality, and DTA-6 treatment is recommended. |