黄翅绢野螟对不同植物的取食和产卵选择

Feeding and oviposition preferences of Diaphania caesalis Walker on different plants

为明确黄翅绢野螟Diaphania caesalis对不同植物的取食和产卵选择性,采用叶碟法、叶面积法和室内观察等方法比较分析了黄翅绢野螟对波罗蜜(‘马来西亚1号’‘海大1号’‘四季波罗蜜’)、榴莲蜜、面包树、大果榕和桑树(‘台湾长果桑’‘粤椹大10’)的取食和产卵选择性,取食面积及初孵幼虫取食不同植物后的存活率。结果表明,黄翅绢野螟1~2龄幼虫对波罗蜜的取食偏好不明显,对不同植物的取食选择率差异不大;随着龄期的增长,3~5龄幼虫逐渐表现出偏好取食波罗蜜。黄翅绢野螟在不同植物上的日均产卵量没有显著差异,偏好在波罗蜜和面包树上产卵,在‘马来西亚1号’波罗蜜上着卵量占所有供试植物上的总产卵量的22.13%。各龄幼虫对不同植物的取食量随着龄期的增加而逐渐增大,5龄幼虫进入暴食期,对3个波罗蜜品种、榴莲蜜、面包树和大果榕的取食量无显著差异,但显著高于2个桑树品种。初孵幼虫取食不同植物48 h后的存活率存在显著差异,取食‘马来西亚1号’波罗蜜存活率最高(98.51%),取食‘台湾长果桑’存活率最低(0.37%)。综上,黄翅绢野螟偏好选择波罗蜜属植物进行取食和产卵,对榕属大果榕存在转移为害潜在威胁,对桑属桑树潜在为害风险较低,研究结果可为黄翅绢野螟在不同植物上的为害风险监测和防控提供参考。

To clarify the feeding and oviposition preferences of Diaphania caesalis on different plants,including three jackfruit varieties(‘Malaysia no.1’‘Haida no.1’‘Four-season jackfruit’),Artocarpus integer,Artocarpus altilis,Ficus auriculata,and two mulberry varieties(‘Taiwanchangguosang’and‘Yueshenda10’),the leaf disc method,leaf area method,and laboratory observation were used to compare and analyze feeding and oviposition selectivity,feeding area,and the survival rate of newly hatched larvae feeding on different plants.The results showed that the feeding preference of the 1st-and 2nd-instar larvae of D.caesalis on jackfruit was not obvious,with no significant differences in feeding selection rates among different plants,but the 3rd-to 5th-instar larvae preferred to feed on jackfruit.There were no significant differences in daily average number of eggs laid by female D.caesalis on different plants,though females tended to prefer laying eggs on jackfruit and A.altilis,particularly on‘Malaysia no.1’,accounting for 22.13%of the total number of eggs laid on all plants.With the increase of instar,the feeding amount of D.caesalis on different plants gradually increased,with the 5th-instar larvae showing the highest food intake.While there were no significant differences in the feeding amounts among three jackfruit varieties(‘Malaysia no.1’‘Haida no.1’‘Four-season jackfruit’),A.integer,A.altilis and F.auriculata,the feeding amounts were significantly higher than those on the other two mulberry varieties.There were significant differences in the survival rates of newly hatched larvae after feeding on different plants for 48 hours,with individuals feeding on‘Malaysia no.1’showing the highest survival rate(98.51%),while those feeding on‘Taiwanchangguosang’had the lowest survival rate(0.37%).Overall,D.caesalis have a much higher feeding and oviposition preference for plants in Artocarpus genus,have a risk of transfer to F.auriculata,and a low risk to mulberry.These results provide a reference for risk monitoring and prevention/control against D.caesalis on different plants.