RESEARCH COMMUNICATIONS CURRENT SCIENCE, VOL. 110, NO. 11, 10 JUNE 2016 2155 *For correspondence. (e-mail: ballalchandish@gmail.com) The new invasive pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in India and its natural enemies along with evaluation of Trichogrammatids for its biological control Chandish R. Ballal*, Ankita Gupta, M. Mohan, Y. Lalitha and Abraham Verghese ICAR-National Bureau of Agricultural Insect Resources, Bellary Road, Bengaluru 560 024, India The South American tomato moth Tuta absoluta (Meyrick) is a devastating pest of tomato. In the pre- sent study Tuta-adapted strains of Trichogramma were evaluated. Amongst the three species, Trichogramma achaeae Nagaraja and Nagarkatti, Trichogramma pre- tiosum Riley and Trichogrammatoidea bactrae Naga- raja could parasitise T. absoluta eggs and the parasitism rates were 5.0%, 51.1% and 68.2% respec- tively. Adults emerged from the parasitized T. abso- luta eggs (4.8%, 97.5% and 90.0% adult emergence respectively). The F1 generation adults of T. pretiosum could parasitise 29% of Corcyra cephalonica Stainton eggs, while the other two species were not successful in parasitizing. In addition, four ‘hymenopteran’ parasi- toids, viz. T. achaeae, Neochrysocharis formosa (West- wood), Habrobracon sp. and Goniozus sp. were also observed to be associated with T. absoluta in the fields during the surveys undertaken in southern India. Keywords: Invasive pest, India, natural enemies, Tuta absoluta. TUTA ABSOLUTA (Meyrick) originated from South Amer- ica; however, the type specimen for T. absoluta was col- lected from the Andean region of Perú. From 2006 to 2015, this pest crossed several borders, devastating to- mato production in both protected and open fields in sev- eral countries, viz. Spain, France, Italy, Greece, Malta, Morocco, Algeria, Libya, Turkey, Syria, Lebanon, Jor- dan, Iraq, Iran, Saudi Arabia, Yemen, Oman, Egypt, Su- dan, Ethiopia and Senegal. In November 2014, this pest was first detected infesting tomato fields in Pune, Maharashtra and subsequently in other districts, viz. Ahmednagar, Dhule, Jalgaon, Nashik and Satara 1,2 . Tuta absoluta has a high reproductive capability and is known to cause damage throughout the entire growth cycle of tomatoes. Our studies indicate that there are 10–12 gen- erations in a year in favourable conditions. Even up to 100% damage has been recorded in different countries. In Karnataka, the pest was first observed in Bengaluru and Kolar areas 3 . If the pest is not curtailed, tomato farmers along with ketchup, sauce and puree industries in our country, will face serious threat. Extensive surveys were conducted in Karnataka, Tamil Nadu and Gujarat by ICAR-National Bureau of Agricul- tural Insect Resources (ICAR-NBAIR), Bengaluru from January to March 2015. In Tamil Nadu, fruit damage by T. absoluta ranged between 0.5% and 13.5%; in Karna- taka 2.0% and 100% and in Gujarat 5% and 12% (Table 1, Figure 1). In Kolar district, slight damage was also re- corded on potato leaves. The occurrence of this pest in tomato fields at different growth stages, recorded at vary- ing levels of infestation in four states, indicates that this pest is a great threat to our tomato farmers, right from the nursery stage of the plants till the harvesting stage. Egg, larval and adult stages of the pest could be recorded in the field (Figure 2). The larvae were observed to mine in- to the apical buds, tender new leaflets, flowers and they bore into the stems and green fruits. The characteristic large galleries caused by the larvae in the leaves, blisters caused by the galleries and the faecal matter within the blisters could be observed in the infested fields. The feed- ing leads to necrosis and drying of plant parts, and in cases of severe infestation, drying of entire fields. Fruits infested by T. absoluta could be identified by presence of characteristic pin holes. The damage generally attracts secondary pathogens leading to fruit rot. The ICAR-NBAIR laboratory and net house studies in- dicate that under Bengaluru conditions, the pest can com- plete its life cycle in 21–23 days. Eggs are cylindrical and creamy white in colour and are laid singly or in small groups (Figure 2 a–c) on the surface of the leaves, buds, stems and calyx of young fruits. Neonate larva mines the leaf, stem or fruit (Figure 2 e). Incubation period is around seven days. Freshly hatched larvae are light yel- low to green in colour. As the larvae mature, they turn dark green in colour. The characteristic dark band poste- rior to the head capsule of the larva help in identifying this pest (Figure 2 f ). There are four larval instars, and the larval period is completed in eight days. Pupation occurs in a silken cocoon, either in the soil or on the leaf surface, within mines or among plant debris (Figure 2 g–i). Pupal period lasts for ten days. Adults are silvery brown with black spots on the fore wings (Figure 2 j). One female moth is known to lay up to 300 eggs. The present study highlights potential natural enemies, identified and evaluated for field use to tackle this noto- rious pest through biological control. The infested plants in tomato fields in Karnataka were examined for presence of indigenous predators. A large population of the mirid bug Nesidiocoris tenuis (Reuter) (Figure 3 a) (10–30 per plant) was observed to be associated with T. absoluta in all the fields. This predator is utilized extensively as a major natural enemy of several insect pests (including T. absoluta) on tomato crops, especially in Mediterranean regions 4,5 . This species is zoo-phytophagous and there are stray reports that they can damage tomato plants