茶芽枯病的研究

茶芽枯病是浙江省茶树土的一种重要病害。为害春茶幼嫩芽叶,可使春茶减产约30%,而且品质下降。病原是一种叶点霉属真菌新种,学名为 Phyllostictagemmiphilae Chen et Hu sp.nov.。菌丝生长和器孢子萌芽的适温在20—27℃,8—10℃时能缓慢生长,29℃时生长受抑制。器孢子萌芽最适 pH 为5.40—6.80。在2%茶汤中器孢子萌芽率最高。病菌对氮源的利用力高,以丙氨酸和谷氨酸最适宜。碳源以果糖、棉子糖、蔗糖为最适宜。病菌以菌丝体或分生孢子器在树上老病叶或越冬芽叶中越冬,器

Studies on Tea Bud Blight(Phyllosticta gemmiphilae Chen et Hu sp.nov.)

Tea Bud Blight is an important and serious disease of tea bush in Zhejiangprovince.It damages the young leaves and shoots.the yields in the spring period maybe decreased as much as 30%.Besides,the quality is decreased also.The causalpathogen is a new species of fungus of genus Phyllosticta(Phyllosticta gemmiphilaeChen et Hu sp.nov.)The optimum temperature of the spore germin ation and themycelium growth is within the range of 20-27℃,it grows slowly in the low temperat-ure of 8-10℃,and is inhibited at 29℃,The optimum PH of the spore germination iswithin the range of 5.4-6.8.The percentage of the spore germination is maximumin the 2% tea infusion.The optimum nitrogen souces for the growth of pathogen areanaline and glutamic acid,and the optimum carbon sources are glucose,fructose andraffinose.The pathogen is overwintered in the old leaves and buds on bushes withthe mycelium and pycnidium.The pycnidiospores is disseminated via the rains anddews.The incubation period is 2-3 days.This disease is ocured only in the springtime,it begins in the end of March,and reaches to the peak in the middle of Aprilto the middle of May.It creases to develop in the middle of June,when the maximumtemperature raises to 29 C.There are a certain degree of differences in the resistanceto disease among the different varieties.The development of disease can be controlledeffectively by the integrated measures of applying the 1000 X dilutions of 50%Benomyl or the 1500 X dilutions of 70% Thiophanate-Methyl in the sprouting periodof spring tea and the begining period of disease development respectively and pluckingthe shoots in turn and in many times.By using these methods,the economicbenefits can be gained significantly.