ELUCIDATE THE ROLE OF GLUCANASE GENE AGAINST FUNGAL PATHOGENS

Abstract

Fungal pathogens are one of the serious devastating agents limiting crop yield to a great extent. Premier management practices to tackle these diseases are the development of disease resistant varieties, application of appropriate fungicides, use of biocontrol agents, plant-based extracts and induction of innate host resistance. These management practices are of great value but have certain limitations i.e., side effects, high cost and decreased efficiency. Resistance development against the fungal pathogens inspired the scientists to explore modern techniques and produce plants with broad spectrum resistance against fungal pathogens. Transgenic technology holds a great potential in this regard. The advancements in molecular biotechnology have enabled the scientists to identify, isolate and characterize the plant stress responsive genes for plant transformation and also explained their role to combat stresses. Trichoderma harzianum is a potential biocontrol agent successfully employed for the control of many economically important pathogens. The biocontrol activity of Trichoderma spp. is majorly attributed to chitinolytic and glucanolytic enzymes having ability to degrade chitins and glucans. Glucanases are therefore one of the key groups of enzymes involved in mycoparasitism. They are classified on the basis of glucosidic linkage, they cleave i.e. α-1, 3-glucanases, β-1, 3-glucanases, α-1, 4-glucanases, β-1, 6-glucanases. The present review aims to explain the role of glucanase genes in the plant defense system and elaborate how glucanase genes protect plants from pathogens.