Abstract:

Liquid and soil culture experiment at 3 phosphorus levels were conducted to study the acid phosphatase (Apase) and secreted Apase activity of 5 Masson Pine provenances and further illustrate their adaptive mechanisms to phosphorus deficiency and relationship with phosphorus efficiency. The results indicated that phosphate starvation would intensively stimulate the release of Apase by root of seedlings. The Apase activity secreted by root in Wuping of Fujian and Xinyi of Guangdong was found to be stronger, and that in Chunan of Zhejiang and Chongyi of Jiangxi was the weaker, which was only about half of Wuping of Fujian. Apase activity in seedling root and leaf increased obviously under low phosphorus stress during growth peak period, showing negatively related to phosphate supply. In general, the Apase activity of root system was stronger than that of leaf. The statistic analysis showed that there existed marked differences among provenances tested for Apase activity in root and leaf under phosphorus starvation. Likewise, Wuping of Fujian and Xinyi of Guangdong had stronger activity, which were thought to be excellent provenances adapted to low phosphorus environment with stronger photosynthesis and higher phosphate efficiency. Apase activity of seedling was found to decline so drastically after growth peak period that there were no obvious differences among all provenances tested.

Key words: Pinus massoniana, provenances, low phosphorus stress, Apase activity