Host range expansion of Helicoverpa armigera to apple orchards in the Himalayan region.

Helicoverpa armigera is an important polyphagous pest of agriculture worldwide. In the current study, the pest has been found to diversify its host range to apple in Himachal Pradesh (India). Currently, H. armigera is found in almost all continents except Antarctica as per CABI and EPPO report and it feed over 300 crops making it a highly damaging and polyphagous pest. In apple orchards of Northern Himalayan region, the larvae were found damaging leaves and young fruits. The present study reveals the current status of infestation and overall mean infestation was observed to be 32.31% in the apple orchards with a range from 12.09 to 41.44%. The lowest infestation of 12.09% and maximum infestation of 38.22% was found during pea stage and lowest infestation of 18.03% and maximum infestation of 41.44% was recorded in case of walnut stage in different apple orchards. Since, apple is a major horticultural crop of Himachal Pradesh and this pest may pose a threat to the economy of apple growers in near future. Ecological versatility, global climate changes, injudicious use of insecticides, advanced detoxification mechanisms and changing farming practices may be responsible for the expanded host range of H. armigera. Therefore stakeholders need to implement various management practices against this pest so that upcoming losses may be avoided.