Teak (Tectona Grandis L.f.) root trainer nurseries: Diseases and their management

Abstract

Introduction of root trainer technology for raising Teak planting stock has had a major impact on seedling production system as well as nursery and plantation management as a whole. Even though, the new technology offers various advantages over the conventional nursery techniques, there is a paucity of data on status of seedling health in root trainers. A systematic disease survey was carried out in seven Teak root trainer nurseries in the Kerala State during 2000-2004. The study revealed that Teak root trainer seedlings were almost free from soil-borne fungal diseases. Often seedling congestion in root trainers led to foliage infection by pathogens, Alternaria alternata, Colletotrichum gloeosporioides, Curvularia lunata, Pestalotiopsis maculans, Phoma glomerata, P. eupyrena, Phomopsis tectonae, P. variosporum, Rhizoctonia solani etc. In general, severity and spread of foliage infection caused by most pathogens was low in all the nurseries surveyed, except leaf blight caused by Phoma glomerata. Bacterial seedling infections by Psuedomonas tectonae were the major threat to the planting stock in most nurseries. Management of foliage disease was possible by application of fungicides (Mancozeb @ 0.2% a.i. / Carbendazim @ 0.1% a.i / Carboxin @ 0.1% a.i). Bacterial infections were controlled by application of Plantamycin/ Oxytetracycline/ Streptomycin sulphate + Tetracycline hydrochloride @ 1000 ppm.