STUDIES ON SYMPTOMATOLOGY OF DIE-BACK OF MANGO STONE GRAFTS

The die-back of mango stone grafts incited by Colletotrichum gloeosporioides Penz, and Botryodiplodia theobromar Pat. either alone or in combination is major disease syndrome widely prevalent in Konkan region of Maharashtra state. The disease mainfestation was enhanced in combination of pathogens.

The symptoms incited by C. gloeosporioides included the development of dark brown circular or irregular spots on leaves resulting into elongated black necrotic patches. The development of shot holes. Crinkling of leaves, drying and shreding of leaves and finally severe shedding of leaves was observed. The development of acervuli was observed on affected shoots. B. theobromae caused the internal discolouration and external darkening of the tender shoots and bark.

The development of die-back was mostly faster from the leaf tip towards petiole through midrib. The affected leaves turned yellowish brown and rolled upwards. The affected shoots became dark shrivelled and shedding of leaves was observed. The pycnidial bodies were developed on the affected parts.