Abstract:

Soil culture experiment at 3 phosphorus levels was conducted to illustrate differences of phosphorus efficiency (PE) between five Pinus massoniana provenances which showed different responses to phosphate fertilizer, and to screen special characteristics indicating PE. The results showed that there existed great differences in PE for provenances tested, among which Wuping of Fujian (distributed over the southern end of Wuyi mountains) was regarded as tolerance provenance to low phosphorus stress with the greatest PE, P absorption and use efficiency, and highest dry matter accumulation under low phosphorus level. PE of Wuping of Fujian was above 70% and about one times higher than those provenances with lowest PE. Among three southern provenances tested, Xinyi of Guangdong was also found to have greater PE. PE was significantly and positively related to P use efficiency, not related to P absorption. The provenances with higher PE had greater dry matter accumulation. PE has a high and positive correlation to root parameters such as root volume, number and total length of lateral roots, and number of fibrous roots under low phosphorus stress. Based on the results of soil and liquid culture experiments, the root parameters above, organic acid amount excreted from roots, and Apase activity etc. can be screened as the special characteristics for PE of P. massoniana provenances under low phosphorus stress.

Key words: Pinus massoniana, provenance, low phosphorus stress, phosphorus efficiency