Biological control of weeds using fungal natural enemies : a new technology for weed management in tea?

Abstract

Tea (Camellia sinensis) is particularly susceptible to competition by weeds, and implementation of controlpractices requires considerable inputs from the farmer. Biological control (BC) using fungal natural enemies offers a sustainable, environmentally friendly and cost effective alternative strategy for the control of weeds. Two approaches can be considered in this strategy: classical biological control (CBC) of invasive alien weeds using their coevolved natural enemies, from the centre of origin of the weed; and inundative control using those pathogens that can be mass-produced, and which are already present in the country where the weed is a problem. The BC potential of 22 important weeds in tea in Asia is presented; it includes four weeds where CBC has already been successfully implemented somewhere in the world. A case study on the CBC of the invasive alien weed Mikania rnicrantha, using the coevolved rust fungus Puccinia spegauinii (from Latin America), in the Assam tea-growing region of India is discussed.