Analysis On The Climatic Causes Of Southern Rice Black-streaked Dwarf Virus Occurrence In Pucheng County In2010

In2010, Southern rice black-streaked dwarf disease broke out large areas in Pucheng County, bringing about huge damage for rice production. According to preliminary analysis, there were several reasons for the acceleration and spread of the disease. First, the method of mixed planting of single and double-cropping rice was in favor of virus spreading and multiplication of Sogatella furcifera, provided them sufficient and edible host plants. Second, from March to June, the low temperature, a large amount of rainfall of strong precipitation intensity and the beginning time of rainy season early, made for a relatively bad agro-meteorological condition. Additionally, the frequent occurrences of such meteorological disaster as hailstorm, rainstorm and flood did harm to the growth of rice and the improvement of disease resistance. What’s more, in May, continuously vigorous warm wet air flows from the southwest provided main power for the flowing of Sogatella furcifera. It had affected not only their migratory direction, but also their immigration peak and amount. From May to June, the apt temperature and wet and rainy weather provided favorable conditions for Sogatella furcifera immigration and settlement. And the immigration peak was matched with the vigorous growing period of rice, which provided adequate food for the Sogatella furcifera. At last, prolonged raining days brought down the control effect, so Southern rice black-streaked dwarf virus and their vectors Sogatella furcifera accumulated in the early rice or other host plants. Thus, a large number of Sogatella furcifera invaded the fields of middle and late rice, caused the infection of the rice and broke out the Southern rice black-streaked dwarf disease in large areas.