Detection of Fungal Pathogens Associated with Forest Tree Seeds

Abstract

Seeds are regarded as highly effective means for transporting plant pathogens over long distance. Compared to seed borne disease problems of agricultural crops, research has been limited on seed borne pathogens of forest tree species and its management practices. Various fungal species (Alternaria, Botryodiplodia, Aspergillus, Trichoderma, Curvularia, Fusariumetc.) are commonly associated with seeds of many forest tree species. Most of seed borne pathogens of trees affect nursery seedlings and reduces seed germination and seedling vigor, also cause deformation, decay or destroy viability of seeds. The present study was carried during 2012 and 2013 at Department Plant Pathology, ASPPE College of Horticulture and Forestry, N.A.U., Navsari to investigate the fungal microorganisms associated with forest tree seeds. Seeds from different forest trees like Teak (Tectona grandis), Subabul (Leucaena leucocephala (Lam.) de Wit.), Gulmohar (Delonix regia (Boj.) Raf., Mangium (Acacia mangium), Ratangunj (Adenanthera pavoninaLinn) and Garmalo (Cassia fistula Linn) were collected from ACHF College, NAU, Navsari. Two methods viz., standard blotter technique and agar plate method (ISTA) were employed for both sterilized and non-sterilized seeds. The results revealed that maximum number of microorganisms and their per cent incidence were higher in non-surface sterilized seeds (NS) than surface sterilized (SS). The microorganisms like, Alternaria, Aspergillus sp., Fusarium sp. and Trichoderma sp. were found to be most frequently occurring fungus. Moreover, the occurrence of different fungi was more on blotter method in all the tested seeds of forest trees.