Rice black-streaked dwarf disease has remained relatively mild in recent years, particularly in the rice-wheat cropping regions, and has not received enough attention. However, the unusually warm winter last year significantly reduced the mortality rate of overwintering ash-gray grasses and weeds, leading to a higher population of residual insects in the fields. After a period of reproduction from mid-March to early May, the number of affected areas increased substantially, with more than 100,000 empty rice plants per mu. Recently, the presence of the rice black-streaked dwarf virus was detected in Waseda, indicating that the city now has a local source of the disease. With the harvest of wheat and the growth of host weeds, the A. sibiricus (gray hopper) adults have begun to migrate into early rice fields, single-season late rice fields, and directly infest paddy fields, spreading the virus further. According to a survey by the Zhejiang Provincial Bureau of Plant Protection and Quarantine, the incidence of gray rice blast is generally high across the province, with some areas reaching or exceeding 12% of the pandemic threshold. Therefore, all localities must recognize the serious threat posed by this disease.
Currently, prevention and control efforts in Putian and Honda focus mainly on managing the first generation of gray hoppers and earthworms. For this, pesticides such as fipronil (1g of 80% fipronil), 25% imidacloprid (used for Bordet, first net), and others with good persistence are recommended. Additionally, fast-acting insecticides like chlorpyrifos (48% Xinyijia, 40% attack) and mixtures containing isoprocarb, aldicarb, and dichlorvos can be used together. Two to three days before transplanting, it is advisable to apply these insecticides to the field to ensure effective pest control during the transplanting stage.
In the early stages of Honda rice cultivation, proper prevention and treatment of gray hoppers and rice blast should be carried out. In direct-seeded paddy fields, applications should be made 7–10 days after sowing (Sui Miao Lu Qing). For transplanted rice, treatment usually begins about 10 days after transplanting, combined with the control of rice leaf rollers and borers, followed by a second treatment after another 10 days. After July, due to high temperatures, the population of ash hoppers and rice blast will naturally decrease, and the need for specific control measures may no longer be necessary. In areas prone to rice black-streaked dwarf disease, it is recommended to use bacteriocin or other viral inactivators 1–2 times during the growing season to enhance the plant’s resistance to the virus and reduce the risk of infection. It is important to alternate pesticide use to prevent resistance development and ensure safe application of chemicals like chlorpyrifos and dichlorvos.
Sour And Spicy Flavored Kimchi
Sour And Spicy Flavored Kimchi,Spicy Cabbage,Spicy Cabbage Korean,Sour And Spicy Sauce Kimchi
Yanbian Jingangshan Food Co., Ltd , https://www.ybjgsfood.com