关键词: 梨, 梨, ISSR-PCR, 正交设计

Abstract: in order to reveal the precipitation characteristics of Xinzhou in summer (6~8 months) under the influence of El Nino events, the author applied the precipitation data of 14 stations in Xinzhou city during 1981~2015 (6~ August), and analyzed the difference between summer precipitation and precipitation in Xinzhou during the start and end of the El Nino event. The analysis results show that: Xinzhou City, summer drought and El Nino have extremely close relationship. (1) El Nino events have a certain degree of impact on the summer precipitation in Xinzhou; the event is the start of the El Nino event in most of the summer drought in Xinzhou. El Nino began the 2008 Xinzhou summer drought probability is 72.7%; the probability of drought was 45.4%. El Nino events over the end of the year are mostly normal or slightly more than the Xinzhou summer rainfall. The probability of the occurrence of severe floods in the end of the El Nino event is 30%; the probability of normal or partial waterlogging is 80%. (2) the extreme value of precipitation in the Xinzhou region during the strong El Nino years. Strong El Nino annual and summer precipitation less than normal probability was 76.9%, partial probability was 23.1% in summer precipitation from the flat percentage is less than or equal to 20% of the rate was 66.7%, the summer precipitation from the flat percentage is more than or equal to 20% was 14.3%.