PDF(Pubmed)
Abstract：
Little is known about winter-season parasitism of eggs of the corn leafhopper Dalbulus maidis DeLong (Hemiptera: Cicadellidae), an important pest of maize throughout the Americas. Our study, conducted in Mexico, aimed to characterize winter-season parasitism of corn leafhopper eggs on maize crops cultivated with drip irrigation and on wild grasses that grow on the edges of maize crops when maize is not present. Maize leaves baited with D. maidis eggs were used to trap the egg parasitoids in the field. In the first year (2022), parasitism of D. maidis eggs was investigated in maize fields planted contiguously on different dates (asynchronous planting). In the second year (2023), parasitism of D. maidis eggs was evaluated in edge grasses and in adjacent maize crops planted on the same date (synchronous). The highest percentage of parasitism (53%), percentage of emergence, and total abundance of egg parasitoids were found in asynchronous maize fields. Here, Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae), Paracentrobia subflava (Girault) (Hymenoptera: Trichogrammatidae), and Pseudoligosita sp. (Hymenoptera: Trichogrammatidae) wasps were found parasitizing the D. maidis eggs, with P. subflava being the most abundant. In wild edge grasses, only P. subflava was found, showing low levels of parasitism, while in synchronous maize, P. subflava increased its percentage of parasitism (up to 37%), percentage of emergence, and abundance, during winter. These results suggest that P. subflava acts as an efficient biological control agent of D. maidis in irrigation-grown maize crops during the winter season, and that edge grasses are overwinter habitats for P. subflava.
摘要：
关于玉米叶虱DalbulusmaidisDeLong（半翅目：Cicadellidae）的卵的冬季寄生现象知之甚少，整个美洲玉米的重要害虫。我们的研究,在墨西哥进行，旨在表征玉米滴灌栽培的玉米作物和不存在玉米时在玉米作物边缘生长的野草上的玉米叶斗卵的冬季寄生。用D.maidis卵诱饵的玉米叶用于捕获田间的卵寄生虫。第一年（2022年）在不同日期连续种植（异步种植）的玉米田中研究了D.maidis卵的寄生现象。第二年（2023年），在同一日期（同步）种植的边缘草和相邻玉米作物中评估了D.maidis卵的寄生性。寄生率最高(53%)，出现的百分比，在异步玉米田中发现了大量的卵寄生虫。这里,AnagrusvirlaiTriapitsyn（膜翅目：Mymaridae），紫草亚黄（Girault）（膜翅目：赤眼蜂科），和假单胞菌。（膜翅目：Trichogrammatidae）发现了寄生在D.maidis卵中的黄蜂，P.subfla是最丰富的。在野草边缘，只有P.subflava被发现,显示出低水平的寄生虫，而在同步玉米中，P.subflava增加了其寄生虫的百分比（高达37％），出现的百分比，和丰富，在冬天。这些结果表明，在冬季灌溉种植的玉米作物中，P.subflava是D.maidis的有效生物防治剂，边缘草是亚黄假单胞菌的越冬栖息地。
