玉米锈病的研究

玉米锈病是一种玉米上常见的气传病害,在中国华南、西南、华北、东北、华东以及西北地区均有发生。其主要侵染玉米叶片,严重时也可侵染玉米果穗、苞叶乃至雄花;在发病中度的田块,可减产10%～20%,感病较重的则可达到50%以上,部分地块甚至绝收,对中国部分玉米产区造成严重影响。应从玉米锈病的抗病机制方面进行研究,引进国外抗玉米锈病的种植资源,筛选抗原,并进行种质资源创新,培育抗病性和丰产性俱佳的玉米新品种,形成以选育抗病品种为核心,以农业防治和化学防治为辅助的综合防治体系,减轻玉米锈病给生产造成的损失。

Research on Corn Rus

Corn rust is a common air-spread disease in corn,which has occurrence in southern,eastern,northern,southwest,northeast and northwest regions in China.It mainly infects the corn leaves,and can also damage corn ear,bracts and male flowers of corn under severe condition.In the fields with moderate occurrence,the yield can be reduced by 10%-20%,which can reach over 50% in the seriously affected fields,some fields even fail to harvest.The disease has caused serious effect on some corn-producing areas in China.Corn rust can be divided into 4 types,including common rust,southern rust,tropical rust and stem rust.Common rust is widely distributed in the corn-producing areas all over the world,and the pathogen is Puccinia sorghi Schw.;southern rust is mainly occurred in the places with low latitudes,and the pathogen is Puccinia polysora Unedrw.;tropical rust is mainly distributed in America,and the pathogen is Physoplla zeae（mains） Cumm ins and Pamaxhar;stem rust is only reported in Tanzania and the United States of America,and the pathogen is Puccinia giaminis Pers.Corn rust occurred in China mainly contains common rust and southern rust.Corn rust mostly occurs in the late growth stage of corn,which generally is harmless.However,it can cause serious disease in some inbred lines and hybrids,make the leaves withered ahead of time,causing serious losses.In the initial stage of incidence,there areonly light yellow long oval brown small pus blisters scattered on both sides of leaves,then small blisters rupture,spilling out rust powdery substance,namely urediospores.In the late stage of incidence,black near circular or oblong protuberances are grown on the lesion,the teliospores are exposed after cracking.Corn rust formerly only damage the corn-producing area in southern China,but its occurrence area and damage degree recently has the aggravating trend from south to north year by year.Therefore,we should study the resistant mechanism of corn rust,introduce the germplasm resources with resistance against corn rust from abroad,screen the antigen and innovate the germplasm resources to breed new corn varieties with good disease resistance and high yield,so that form the integrated control system with selecting resistant varieties as the core,agricultural control and chemical control as auxiliary,and finally reduce the yield losses caused by corn rust in production.