苜蓿施磷对牛角花齿蓟马产卵选择、生长发育的影响

Effect of phosphorus application to alfalfa on oviposition selection,growth and development of Odontothrips loti

为探索苜蓿施磷后对牛角花齿蓟马(Odontothrips loti)产卵选择、生长发育及苜蓿抗蓟马的影响,以苜蓿品种甘农3号和甘农9号为试验材料,观察了牛角花齿蓟马成虫在不同施磷水平下苜蓿叶片上的产卵量及其若虫的生长发育状况,并测定了不同施磷水平下苜蓿叶片的可溶性糖,氮和磷含量。结果表明:在同一苜蓿品种叶片上,随着施磷水平的增加,牛角花齿蓟马的产卵量显著增加;施磷后,牛角花齿蓟马1~2龄若虫成活率显著升高,但发育历期无显著变化,3~4龄若虫成活率和发育历期均无显著变化;随施磷量的增加,苜蓿可溶性糖含量,磷含量及糖氮比显著增加,三者与蓟马在苜蓿叶片上的产卵量之间呈不显著相关关系,甘农9号的磷含量与蓟马1~2龄若虫成活率之间具有显著的正相关关系。施磷后两个苜蓿品种对牛角花齿蓟马无显著的抗生性和排趋性。

Two alfalfa varieties(Gannong No.3 and Gannong No.9)were used to investigate the effect of phosphorus application on oviposition selection,growth and development of Odontothrips loti,and the resistance of alfalfa to thrips.The egg laying amount of adults,growth and development of nymphs under different phosphorus levels were observed.The soluble sugar content,nitrogen content and phosphorus content were determined as well.The result showed that the egg laying amount of thrips on the leaf of same alfalfa variety increased significantly with the increase of phosphorus level.The survival ratio of 1-2 instar nymph increased significantly after phosphorus application,but the developmental period did not change significantly.There was no significant changes in 3-4 instar nymph survival ratio and developmental period.The soluble sugar content,phosphorus content and sugar to nitrogen ratio of alfalfa were significantly increased after phosphorus application and there was no significant correlation with egg laying amount,there was a significant positive correlation between phosphorus content and 1-2 instar nymphs survival rate of Gannong No.9.Two alfalfa varieties did not show significant antixenosis and antibiosis to thrips after phosphorus application.