International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 8 (2013) pp. 187-195 
Hypersensitive reaction and anatomical changes of young tea leaf (Camellia sinensis, clone TV1) during feeding by tea mosquito bug (Helopeltis theivora Waterhouse: Hemiptera: Miridae) 
Parveen Ahmed1 *, Prasenjit Bhagawati1 , Saurabh Kr. Das1 , M.C. Kalita2 and Sudripta Das1 
1Department of Biotechnology, Tocklai Experimental Station, Jorhat, India 2Departrment of Biotechnology, Gauhati University, Guwahati, Assam, India *Corresponding author e-mail:  
This work mainly deals with some aspects of early morphological and structural changes induced during feeding by Helopeltis theivora on young tea leaves (Camellia sinensis) clone TV1.Infestation of tea leaf by the insect induced hypersensitive reaction which appeared to be similar to that induced by microbial pathogens in plants. The pest is a vascular feeder and the labial stylet pierces protective wax layer, cuticles, epidermal and underlying cells to reach the thin- walled phloem cells and sucks the cell sap. Sap feeding induced hypersensitive reaction resulting formation of typical lesions probably due to release of elicitor with the saliva of the feeding insect. Feeding caused erosion of the wax layer, cuticle and epidermal cells and browning of the cells along the course of the piercing stylet and nearby tissues. Phloem cells, from which the insect sucked sap, did not discolour but collapsed earlier than other cells. Ultrastructural changes evident before collapse of affected cells were collapse of vacuole, degenerative changes in chloroplasts, damage to the cell membrane and cell wall. 
Tea; Helopeltis theivora; hypersensitive reaction; lesion; Camellia sinensis; anatomical change.