Taro Root Aphid

📖 Description

The Taro Root Aphid (Pentalonia caladii) is a small but economically important aphid of Indian Araceae and Musaceae crops — particularly taro (Colocasia esculenta) and banana (Musa spp.). The species is best known not for the direct feeding damage it causes (which is generally moderate) but as the principal vector of Banana Bunchy Top Virus (BBTV) — the most destructive viral disease of banana worldwide. BBTV has destroyed banana plantations across the entire tropical world; in India, the virus is endemic in the banana-growing belts of Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Maharashtra, Gujarat, and West Bengal, causing an estimated 10–30 % yield loss annually (with peak losses exceeding 80 % in heavily infested smallholder plantations in Kerala and Tamil Nadu). The Pentalonia aphid feeds on banana by inserting its stylet into the phloem sieve tubes of the leaf axils — the protected, sheltered environment of the leaf axils is ideal for aphid colony development, but also makes contact insecticide sprays largely ineffective because the spray cannot reach the aphids. Management of BBTV therefore depends primarily on (1) using certified virus-free tissue-culture plantlets for new plantings, and (2) roguing and burning all infected plants immediately on detection — these cultural measures break the virus-aphid-plant transmission cycle. The Indian Council of Agricultural Research’s National Research Centre for Banana (NRCB, Tiruchirappalli) maintains India’s national BBTV surveillance programme and has developed the ‘clean-seed’ programme that supplies certified virus-free tissue-culture banana plantlets to smallholder growers across peninsular India. On taro, the aphid’s economic impact is more direct — heavy root infestations reduce corm yield and quality, particularly in the Colocasia-growing belts of Kerala, Karnataka, Tamil Nadu, Andhra Pradesh, and Odisha where taro is a critical food-security crop.