leaf miner, Tutaabsoluta (Myrick, 1997) (Lepidoptera:Gelechiidae) is devastating pest of tomato (Lycopersicon esculentum Miller). This oligophagous pest associated with solanaceous crops can reduce yield and quality of tomato in newly invaded areas 80-100 % both in field and greenhouse conditions if control measures are not applied. Larvae of this pest feed on leaves, buds, stem and fruits of tomato. Fruit rot occurs due to secondary pathogen invasion in fruits bored by the insect.
Tuta absoluta Native to South America has been key pest of tomato in the region since 1960s and was reported in Spain in 2006 and subsequently spread throughout many European and Mediterranean countries. Tuta absoluta has been recorded from India during October, 2014. Since its introduction to India, the possibility of invasion of Nepalese’s tomato farming by the pest was always existed due to open boarder and weak quarantine.
The first record of occurrence of this pest in Nepal has been reported by Ajaya Shree Ratna Bajracharya (Senior Scientist, Entomology Division, NARC) and his team from a tomato farm of Tarakeshwor Municipality, (27o44.661' N latitude and 85o18.895' E longitude) of Kathmandu in 3rd May 2016. Mr. Bajracharya and his team identified the pest scientifically studying external morphology and genitalia of male moth. Further confirmation of the pest was done with help of Division of Entomology, IARI, New Delhi, India. The different stages of the pest is given in Fig 1. A survey conducted within Kathmandu valley and vicinity showed this pest has been spreading from Kathmandu valley into surrounding areas. The distribution map of the pest is shown in the Fig 2. This pest is recorded from Kathmandu, Lalitpur, Bhaktapur, Kavrepalanchowk and Dhading districts.
Fig 1. Egg, Larva , Pupa and adult of Tuta absoluta.
Fig2. Distribution map Tuta absoluta in Kathmandu valley and its vicinity.
This pest can damage leaf, apical stem and fruits. The irregular shaped mines of different size in seen in leaf. The stem boring cause leaves stunted growth with dark frass in apical stem. The fruits are bored specially near to calyx and other hidden pars. The damage symptoms are given in Fig 3.
Fig 3. Damage symptoms of Tuta absoluta on leaf, apical stem, fruit and damaged field.