The Study On The Occurrence And Control Of The Diseases And Pests On Cinnamomum Cassia In Fujian

Cinnamomum cassia is a valuable plant. It could be used of medicine, food and perfume, etc. Cinnamomum cassia var macrophylla is an excellent variety. Its quality is better than any other kinds of C.cassia. The Fujian province imported this variety from Viet Nam in late 1950's and now the planted areas get to 866.7 hec. In recent years the diseases and pests have caused big damage to the plantation of this tree and influence their generalization and development seriously. This dissertation make an extensive investigation on the species of diseases and pests. The research about the occurrence regularity and control experiments of some major diseases and pests has been carried out, in hope of finding some means to control them effectively.By primary research it is found that there are eight kinds of diseases and sixteen kinds of pests at least on C.cassia. Of them the Cephaleuros virescens, Polylopha cassiicola, Gibbvalva quadrifasciata and Homoeocerus unipunctatus are major disease and pests.The algae-spot disease is serious and it can propagate and infect by means of zoospore from March to October. It is a single-cycle disease. The pathogen of this disease can survive over winter by means of sporangium on infected leaves. The control effects of 1% Bordeaux mixture, Carbendazim and Topsin are 66.2%,33.8% and 45.9% respectively.The pathogen of swollen-stem disease is uncertain, but it has close relationship with Homoeocerus unipunctatus. The control effect of this disease can not be achieved because the time is limited.The Polylopha cassiicola has seven generations in a year and overwinter by pupa in grass and dead leaves. This pest is popular when the tree is young. The control effects of cutting dead-shoots ,spraying trees with dimethoate and phoxim are 77.2%, 88% and 66.4% respectively.The Gibbvalva quadrifasciata has eight generations in a year and overwinter by pupa in grass and dead leaves. This pest can damage young leaves and bring great loss to the young forest of C.cassia. The control effects of dimethoate and phoxim are 84.5% and 81.4% respectively by spraying them on leaves.