Biological Control with Trichogramma in China: History, Present Status, and Perspectives

Abstract

Trichogramma species make up one of the most commonly used groups of natural enemies for biological control programs worldwide. Given the major successes in using Trichogramma to control economically important lepidopterous pests on agricultural crops in China, the biology and ecology of these wasps have been intensively studied to identify traits that contribute to successful biological control. Since the 1960s, improved mass production of Trichogramma and better augmentative release methods to suppress agricultural pests have been achieved. We review the history of research and development; current knowledge on biodiversity and bio-ecology of the species used; and achievements in mass-rearing methods, release strategies, and current large-scale applications in China. In addition, we discuss potential issues and challenges for Trichogramma research and applications in the future . Expected final online publication date for the Annual Review of Entomology, Volume 66 is January 8, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Temperature Affects Biological Control Efficacy: A Microcosm Study of Trichogramma achaeae

“…Trichogramma spp. are among those most successful biological control agents that have been widely and successfully used in biological control [ 20 , 21 ]. T. achaeae is a recently commercialised species reported as having a high efficacy in controlling the tomato leaf miner, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), a devastating pest in tomato production [ 22 , 23 ].…”

Laboratory and field studies supporting augmentation biological control of oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), using Trichogramma dendrolimi (Hymenoptera: Trichogrammatidae)

“…The higher per‐capita parasitism capability of Trichogramma dendrolimi could potentially enable a similar level of control to be obtained with releases of fewer wasps in comparison to the other species. Aside from differences in host suitability, parasitoid performance would also be influenced by their longevity, dispersal and host searching capacity in specific environmental contexts 9 . According to the previous work, Trichogramma dendrolimi was the dominant naturally‐occurring egg parasitoid in peach orchards, 28 and this was also true in the pear orchard in these field trials.…”

“…Egg parasitoids oviposit in host eggs, hijack the hosts' physiology to support their own development, and ultimately kill the host 15 . Several Trichogramma species egg parasitoids have been successfully used against Lepidopteran pests of crops by inundative application, particularly in borer pest control 8–14 . In China, both Trichogramma dendrolimi and Trichogramma chilonis have been augmented against G. molesta in pear orchards, 16 but their relative efficacy against this pest has not been directly compared.…”

“…Meanwhile, the dispersal capacity of released parasitoids is a key factor in determining the ideal distance between release sites 19–21 . More precise studies of the dispersal capacity of egg parasitoids have become available in recent years 9 . Minute parasitoids normally disperse over small distances, and are vulnerable to the influence of vegetation cover and climatic factors 9,21–24 …”

“…More precise studies of the dispersal capacity of egg parasitoids have become available in recent years 9 . Minute parasitoids normally disperse over small distances, and are vulnerable to the influence of vegetation cover and climatic factors 9,21–24 …”