利用嫩玉米穗饲养大螟的技术

An improved food for rearing the pink stem borer,Sesamia inferens:unripe corn

[目的]提供一种新的饲养大螟的方法,为获得充足的、高质量虫源提供技术保障。[方法]使用籽粒未形成的嫩玉米穗、鲜茭白和市场上出售的成熟甜玉米3种天然饲料分别饲养大螟,对比3种天然饲料饲养下大螟幼虫发育历期、存活率、化蛹率、羽化率、蛹重和单雌产卵量等适合度参数。[结果]大螟在嫩玉米穗上的平均幼虫存活率为85.3%,化蛹率为77.1%,羽化率为66.3%,显著优于茭白和甜玉米的饲养效果。在嫩玉米穗上,大螟世代发育历期为36.2 d,幼虫发育历期为16.6 d,显著短于在茭白和甜玉米上的发育时间。取食嫩玉米穗的大螟单雌产卵量为81.1粒,与野生型大螟的产卵量没有显著差异。[结论]嫩玉米穗可为大螟的生长发育和繁殖提供足够的营养物质,提高了初孵幼虫的存活率,加快了其世代发育速率,可做为一种适宜的饲料用于大螟的大规模饲养。

[Objectives] To develop a new food capable of producing large numbers of high quality S. inferens. [Methods] S. inferens were reared on three kinds of foods, unripe corn, fresh water bamboo and sweet corn, and fitness parameters, survival rates, the durations of different developmental stages, pupal weight, and the number of eggs laid per adult female, of population reared on each food were measured and compared. [Results] The mean larval survival, pupation and eclosion rates orS. inferens raised on unripe corn were 85.3%, 77.1% and 66.3%, respectively, significantly higher than those raised on fresh water bamboo and sweet corn. The developmental duration of a complete generation, and the larval stage of populations raised on unripe corn were 36.2 d and 16.6 d, respectively, which were significantly shorter than those fed on fresh water bamboo and sweet corn. The number of eggs laid per female fed on unripe corn was 81.1, which did not differ significantly from that of females in paddy fields. [Conclusion] S. inferens raised on unripe corn had superior development and fecundity to those raised on bamboo and sweet corn, and individuals reared on unripe corn also had higher neonatal survival rates and faster larval developmental. Unripe corn is a suitable diet for mass rearing S. inferens.