Home › Edible Gardening › Article

What are the control methods for rice bacterial leaf streak?

Edible Gardening 0 views
Rice bacterial leaf streak, or rice fine stripe disease for short, is an important disease in rice production in China. Its pathogen belongs to the genus Xanthomonas, and the bacteria mostly enter through the leaf stomata; symptoms can appear at any growth stage of rice. The lesions are short, fine, narrow stripes, with the striping appearing between the leaf veins. When held against the light, the lesions appear semi-transparent and water-soaked, turning red later; the bacterial masses on the stripes are very numerous, especially on the underside of the leaf, and are not easily dislodged when dry. Because hybrid rice still lacks disease-resistant combinations, and because the disease occurs over a wide area with an uneven distribution, this creates great difficulties for seed quarantine;

Rice bacterial leaf streak, or rice fine stripe disease for short, is an important disease in rice production in China. Its pathogen belongs to the genus Xanthomonas, and the bacteria mostly enter through the leaf stomata; symptoms can appear at any growth stage of rice. The lesions are short, fine, narrow stripes, with the striping appearing between the leaf veins. When held against the light, the lesions appear semi-transparent and water-soaked, turning red later; the bacterial masses on the stripes are very numerous, especially on the underside of the leaf, and are not easily dislodged when dry. Because hybrid rice still lacks disease-resistant combinations, and because the disease occurs over a wide area with an uneven distribution, this creates great difficulties for seed quarantine; high-yield and high-production cultivation practices in turn favor the occurrence of the disease, while for chemical control there is still no very effective pesticide. At present, the main measures for controlling this disease are seed disinfection, seed quarantine, planting resistant varieties and strengthening cultivation management, supplemented by a certain degree of chemical control. After years of experimental research, the Plant Protection Research Institute of the Guangdong Academy of Agricultural Sciences proposed a method of seed disinfection combined with pesticide application at the seedling stage to control this disease. After this technology was implemented, it achieved very good results and can be promoted as a supplementary measure for high and stable rice yields. The specific methods are as follows:

1. In disease-affected areas, disinfect seeds with a 500-fold dilution of TC seed disinfectant, and at the 3-4 leaf stage of the seedlings, spray twice with a 600-fold dilution of BC folpet.

2. When raising seedlings for seedling throwing, disinfect seeds with a 500-fold dilution of TC seed disinfectant, then spray once with a 600-fold dilution of BC folpet at the 2-leaf stage of the seedlings.

3. At hybrid rice seed propagation bases, disinfect seeds with a 500-fold dilution of TC seed disinfectant, spray BC folpet twice during the seedling stage; at the late tillering stage of rice, spray once with a 600-fold dilution of BC folpet. Using the above methods to control fine stripe disease can eliminate the primary infection sources at the key points of disease occurrence, delay the onset of the disease by 7-10 days, stagger the most sensitive disease-susceptible period during rice growth from the peak period of disease occurrence, achieve a control effect of up to 80%, greatly reduce the losses caused by the disease, and recover 8%-15% of yield loss. Because the pesticide is applied at the seed and seedling stages, labor costs and pesticide costs can be greatly saved, reducing control costs by 90%.

Related Articles