Biocontrol of insects, diseases, and weed pests in tea plantation

by Dr. N. G. Hajra | Proc. 15th International Plant Protection Congress. Beijing, China, May 11-16, 2004


Tea plant is an evergreen woody perennial and grown mostly as a monoculture, provides suitable condition for the pests to feed on it and breed. The magnitude of pest infestation varies seasonally depending on altitude, climate, pathogen and cultural practices. It was estimated that the crop loss in tea accounted for anywhere between 6 and 14% due to the ravages of insect pests, and 10 and 15% due to diseases.
The extensive use of chemical pesticides has had many well documented adverse consequences. Therefore, the present trend of pest control is to minimize the use of pesticides with optimum reduction in pest population. There is considerable accent on the biological methods which are integrated with chemical plant protection.
A considerable number of natural enemies of pests have been identified and some of them have been proved capable under ideal conditions. The results of laboratory and field trials with microbial agents that includes bacteria, fungi, viruses, protozoa and nematodes that are pathogenic or antagonistic to insect, plant pathogen and weed pests are discussed. The bioefficacy of neem and other botanicals in controlling insect pests have been evaluated. The use of semiochemicals and oils, and antagonistic microflora in controlling insect pests and diseases of tea are also discussed. The feasibility of using allelopathic properties of certain potential weed species in tea weed management has been explored. Limitation and future course of action for implementation of biocontrol activities have also been discussed.