水稻黄矮病的诊断,通常是凭症状或用接虫传染试验进行。但随着用药、用肥水平不断提高,黄矮病的症状往往和虫伤、肥害、药害、生理性黄叶等混淆,不易得出正确诊断;用接虫传染试验虽然可靠,但又太费时。近年来,我们在 调查时,采用碘—碘化钾溶液来检测叶片中的淀粉,结合发病田块的观察,以诊断黄矮病,收到较好的效果。 用碘诊断水稻黄矮病的原理是:植物受黄矮病毒侵染后,淀粉的运转受到阻碍,叶片内往往积累淀粉较多。用碘来检测叶片中的淀粉,可进行比较可靠的诊断。具体做法是:把怀疑为黄矮病株的发黄叶片剪成小段(取叶片的中、下部为 Yellow dwarf disease diagnosis of rice, usually by symptoms or use of infection test carried out. However, with the medication, the level of fertilizers continues to increase, the symptoms of yellow dwarf are often confused with insect pests, fertilizer damage, phytotoxicity, physiological yellow leaves, etc., and it is not easy to draw a correct diagnosis. Too time-consuming. In recent years, we used iodine - potassium iodide solution to detect the starch in the leaves during the investigation, and combined with the observation of the disease field to diagnose yellow dwarf disease, we received good results. The principle of using iodine to diagnose rice yellow dwarf disease is that the operation of the starch is hindered by the infection of the plant with the yellow dwarf virus and more starch is often accumulated in the leaves. Iodine to detect the starch in leaves, can be more reliable diagnosis. The specific approach is: the suspect yellow dwarf strain of yellow leaves cut into small pieces (taking leaves in the lower part of