玉米粗病是一种病毒病,主要由传毒介体灰飞虱传毒引发,发生的轻重与玉米生育期、生态环境、灰飞虱的暴发期、玉米品种的抗病性等因素有关。1.发病症状多出现在六至七叶期,发病初期在心叶基部的中脉两侧出现透明的虚线斑点,逐渐扩展到整个叶片,并在叶背、叶鞘和苞叶的叶脉上出现长短不一的蜡白色突起,后变黑褐色,用手触摸时有粗糙不平的感觉。发病后的玉米植株生长受到抑制,节间粗肿缩短,严重矮化,一般病株高度只有健株 Coarse maize is a virus disease, which is mainly caused by the transmission vector Laodelphax striatellus. The severity of maize disease is related to the growth period of maize, the ecological environment, the outbreak of Laodelphax striatellus and the disease resistance of maize varieties. 1. Symptoms appear in the six to seven leaf stage, early onset in the central leafbladder at both sides of the midpoint of the transparent dotted spots appear, and gradually extended to the entire leaf, and leaves in the leaf blade, leaf sheath and husk leaf veins on the length of different lengths Wax white protrusions, after the dark brown, rough feeling when touched by hand. After the onset of corn plant growth was inhibited, internode shortening, severe dwarfing, the general plant height only healthy plants