Study on Cone Life Table of Pinus armandii

Pinus armandii is one of important trees for afforestation in Southwest China,and the development of cones from the stage of bud burst to cone lignification are interfered by many biotic and abiotic factors.The cone life table of P.armandii was built based on systematical tracking observation to the whole life history of the cone in Zixi Mountain Forest Base in Chuxiong City,Yunnan Province.During the whole growth phases from bud burst to cone lignification,the cone death percent is 47.6%.Runtishness,pest damage,mechanical loss,frost and rat damage are the 5 fatal factors that result in the death and loss of cone.Among the 5 factors,pest damage is an important and key factors which is the most effective that makes the death rate of cones to be 27.2%.The cone loss because of pest damage is 1.33 times more than that because of other factors.There are 5 important species in the P.armandii seed orchard.The damage of Strobilomyia sp.and Resselille sp.was dominant during the growth phases of 1-year-old cone,and the damage of Dioryctria rubella was the key factor which led to the cone death during the growth periods of 2-year-old cone.