Integrated Approach to Management of Brown Root Rot Disease of Tea (Camellia sinensis (L)O.Kuntze).

Abstract

Abstract: Brown root rot disease caused by Fomes lamoensis and Trott has been identified as the primary root disease of tea. Indiscriminate use of chemicals in tea garden area has an adverse effect on the environment. For management of this root disease, integrated approach is required for sustainability in tea cultivation. The present study involves the use of five systemic fungicides, which were screened and tested against the pathogen. Total five fungicides used, among the fungicides propiconazole and hexaconazole was inhibit 98.51% and 100% growth of pathogen @ 100mg/l concentration. However bavistin, roko and ektino, showed in12.58%, 5.18% and1.48% inhibition respectively. Bacillus cereus and Trichoderma harzianum were also evaluated and efficiently inhibited F. lamoensis in vitro. The zone of inhibition varied from 10 to 15 mm in case of B. cereus and 10 to 16 mm in case of T. harzianum. The nursery experiment exhibited that tea plants at 120 days after the treatment (DAT) with the pathogen showed 76.66% disease incidence. The reduction in disease incidence (23.33% and 13.25% respectively) was observed when the plants were treated with biocontrol agents i.e.B. cereus and T. harzianum. In case of chemically treated plants only 10% disease incidence was observed. The results of the nursery experiment showed that both the chemicals and biocontrol agents significantly affected incidence of disease and promoted growth of tea measured in terms of shoot height, root length, number of new leaves, lateral branches, biomass of shoot and root over the control.