论文部分内容阅读
油茶紫斑病(Cercosporella sp.)是广西近年在病虫害普查中在普通油茶(Camellia oleifenaAbel)上新发现的一种叶部病害,分布于富川、贺县、蒙山、昭平、防城、柳州、柳江、三江、百色、浦北、岑溪等地,危害程度轻至中等。紫斑病主要危害油茶嫩叶。发病初期叶面病斑呈红色或暗红色小圆点,平或稍突起;后变为紫红色,圆形,边缘一圈的颜色较深,略比健部突起,中央部凹陷,背面平坦或稍隆起。病斑大小为0.5—3毫米,定形后一般不再扩展。发病后期病斑边缘一圈呈紫红色,中央部呈暗灰色或暗褐色,多数有圆形小黑点。黑色小点表面开裂后,露出分生孢子梗及孢子,成为霉点。最后病斑坏死,形成穿孔。一叶片可有病斑一至数块,有的多达几十块,布满全
In recent years, Cercosporella sp. Is a newly discovered leaf disease on Camellia oleifenaAbel in Guangxi in the survey of pests and diseases. It is distributed in Fuchuan, He County, Mengshan, Zhaoping, Fangcheng, Liuzhou and Liujiang , Sanjiang, Baise, Pubei, Cenxi and other places, the severity of light to medium. Purple spot the main endangering tea leaves. The early onset of foliar lesions were red or dark red dots, flat or slightly raised; after into a purple, round, darker edge of the circle, slightly protruding than the Department of Health, central depression, flat back or A little bulge. Lesions size of 0.5-3 mm, generally no further expansion after setting. The lesion at the edge of a circle was purple, dark gray or dark brown central part, the majority have round black spots. After the surface of the black dot is cracked, the conidiophores and spores are exposed and become moldy spots. Finally, the lesion necrosis, the formation of perforation. A leaf may have a spot to several pieces, and some as many as dozens, full