Indian Journal of Entomology
Year : 2008, Volume : 70, Issue : 3
First page : ( 273) Last page : ( 277)
Print ISSN : 0367-8288.

A refined damage rate scoring method for tea mosquito bug infestation in cashew

Mahapatro G. K.

Division of Entomology, Indian Agricultural Research Institute, New Delhi-110 012.

Received:  September,  2008.

Abstract

Integrated pest management (IPM) has emerged as the sole solution reasonably relying on need-based spraying to reduce the pesticide-load in nature. The adoption of IPM warrants working out decision support tools like pest population (or damage) monitoring and economic threshold level for the target insect-pest(s). Unfortunately, even after 4–5 decades of long research in cashew on tea mosquito bug (TMB), little attempt has been made in this regard except that by Ambika et al. (1979). Developing such a decision tool is imperative for formulating an IPM strategy in cashew. A concise and critical review is presented in this article in particular on damage rating scales involving TMB with suggestions for refinement. A refined rating scale is advocated based on the occurrence of pest-damage on target tissues; and formulated the Damage Profile Index (DPI, maximum value 100) as the product of Damage Intensity and Extensity of the target insect-pest. Damage Intensity (DI) is the degree of insect-pest infestation onto the target tissues (flushes). This is calculated based on the number of necrotic lesions produced by TMB. Damage Extensity (DE) is the degree of insect-pest infestation onto the target tree/plant. This is calculated based on the percentage of flushes lIffected/infested in the cashew tree/plant.

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Key words

Cashew, Integrated pest management (IPM), Tea mosquito bug (TMB), Damage Rating Scale, Damage Profile Index (DPI).

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