Study on Species Relationship between Pinus massoniana and Castanopsis fissa Using 32P

32P was used to study the absorptivity of the roots from Pinus massoniana and Castanopsis fissa mixed forest and the pure forest of P. massoniana. It showed that the orderof the ability to absorb 32P was C.fissa mixed P. massoniana pure P. massoniana. The results of allelopathy between these two species showed:(1)seven kinds of secretions pro-duced by the root and other organs of C.fissa improved the 32P level of leaves from seedlingsof P. massoniana. Five kinds of secretions produced by the branch,root and other organs of P. massoniana improved the 32P level of leaves from seedlings of C.fissa;(2)the interact ofthe parts above ground of P. massoniana and C.fissa increased the absorbing ability of 32P for 41.1% and 55.8% respectively as compared to their controls.