建平县位于辽西北地区，属大陆性半干旱气候，光照充足，土地资源丰富，适合梨树生长发育的要求，经多年的努力发展，该县已拥有梨树２８３３ｈｍ２，１２７万株，并取得了良好的经济效益。但是，由于近年来梨木虱的严重为害，经济损失严重，对梨树生产威胁较大。为此，建... Jianping County, located in the northwest of Liaoning Province, belongs to the continental semi-arid climate with sufficient light and rich land resources, suitable for the growth and development of pear trees. After years of hard work, the county already has 2833hm2,127 million pear trees and has obtained A good economic benefits. However, due to the serious damage of pear psylla in recent years, the economic loss is serious, which threatens the production of pear trees. For this, build ...