发生与为害情况 在山东湖区一带群众历年播种豌豆-麦面积很大,据试验与调查,混作较单作每亩平均可增产40％以上,特别是在发生春霜冻害的年份,因豌豆抗霜而增产更为显著。 但近年来因豌豆象为害严重,混作面积已逐年缩减。如在金乡、嘉祥两县调查,1955年 Occurrence and Harm Situation In the peasants and peasants planted peasants and wheat in the area around Shandong Lake in the past years, the pea-wheat area is very large. According to the test and investigation, the average yield of peas and wheat increased more than 40% per mu compared with that of single peasant, especially in the years where spring frost damages occurred. The yield is more significant. However, in recent years due to pests severely damaged, mixed area has been reduced year by year. As in Jinxiang, Jiaxiang two counties survey, 1955