COLONIZATION AND PLANT GROWTH PROMOTION IN SOMATIC EMBRYO DERIVED BLACK PEPPER PLANTS BY FUNGAL ENDOPHYTES

Abstract

Black pepper (Piper nigrum L.) plants (variety Sreekara) were produced through somatic embryogenesis and studied for endophytic fungal association and the role endophytic fungi in hardening tissues and its growth promotion. Interestingly, somatic embryo derived black pepper plants are found to be free from fungal association. No Fungus could be obtained from the tissues of somatic derived black pepper plants. The colonization studies on somatic plants by endophytic fungi showed that stem and root tissues were successfully colonized by the inoculated endophytic fungi such as Diaporthe sp., Annulohypoxylon nitens, Daldinia eschscholtzii, Fusarium oxysporum and, Phomopsis sp. The colonization of black pepper tissues by the endophytic fungi were confirmed by re- isolation from the treated plants. Endophyte enriched sterile sand is a promising medium for the hardening of somatic derived black pepper plants with enhanced survival rate of 56% -69% when compared to control (50%). Application of endophytic fungi in black pepper showed a significant increase in growth parameters like plant height, number of leaves, number of nodes, fresh and dry weight of plant in under green house. This is the first report of using endophytic fungi for hardening tissue cultured plants of black pepper