04 Haz 2025 Çarşamba
Tritrophic associations (parasitoids - aphids - plants) and distribution of species of Betuloxys Mackauer, Lipolexis Förster and Monoctonus Haliday (Hymenoptera: Braconidae: Aphidiinae: Trioxini) in India
Abstract : The genera, Betuloxys Mackauer, Lipolexis Förster, and Monoctonus Haliday are exclusively aphid parasitoids. These genera are widely distributed and some species, particularly, Lipolexis oregmae (Gahan) has been successfully used in biological control of the aphids worldwide. All these genera are grouped in the same tribe Trioxini of the subfamily Aphidiinae (Hymenoptera: Braconidae). In India, 4 species of Betuloxys, 3 species of Lipolexis and 4 species of Monoctonus are recorded parasitising 5, 32 and 8 species of aphids, respectively. All species of Betuloxys are monophagous and are distributed in 4 states/union territory. Lipolexis oregmae (Gahan), distributed in 17 states/union territory of India, is highly polyphagous parasitising 22 species of aphids infesting 87 species of food plants mostly agricultural crops and fruit trees followed by Lipolexis gracilis Forster which parasitises 11 species of aphids feeding on 18 food plants. Lipolexis myzakkaiae Pramanik & Raychaudhuri is monophagous. Lipolexis species prefer mostly aphids belonging to the genus Aphis, particularly bean aphid (Aphis craccivora Koch), citrus aphid (Aphis citricidus (Kirkaldy), Aphis aurantii Boyer de Fonsc.), cotton aphid (Aphis gossypii Glover), and spirea aphid (Aphis spiraecola Patch) and green peach aphid (Myzus persicae (Sulzer)) and all these infest several economically important crops in India. Most of the tritrophic associations of Lipolexis oregmae (Gahan) are recorded in Bihar (53 triplets) followed by Uttar Pradesh (27 triplets), Meghalaya (21 triplets), Karnataka (19 triplets) and less than 15 triplets in other states. Species of the genus Monoctonus are almost host specific, each species not parasitising more than two aphids infesting 1-3 species of host plants with 10 tritrophic associations. No species of these genera of aphid parasitoids is recorded in Andhra Pradesh, Chhattisgarh, Gujarat, Haryana, Jhargram, Madhya Pradesh, Maharashtra, Odisha, Rajasthan, Telangana states. Indeed, no attempt has been made to record these natural enemies in almost 86% area of India, and an intensive and extensive survey plan is warranted to record them in those unexplored areas.