Author(s):

Nisar Ahmad Dar, Nisar Ahmad Khan and Mudasir Ahmad Bhat

Abstract: Surveys were conducted to determine the occurrence and distribution of Stem bark canker affecting Apple in Kashmir valley during 2013 and 2014. Apple orchards were more affected in district Ganderbal with highest canker incidence (31.33%) and the least in district Shopian (15.33%). Among the villages surveyed, Watlar of district Ganderbal exhibited the highest canker incidence of 41.00 per cent. Village Batapora of district Shopian exhibited the least canker incidence of 13.00 per cent. The data over the two years further revealed that maximum canker incidence of 23.50% was observed on tree trunks followed by scaffold branches (17.70%) and least on fruiting wood (10.09%). Infected samples were collected from different localities in four districts of Kashmir valley. Stem bark symptoms mostly characterized under field conditions by the appearance of small, sunken, reddish brown lesions, which on enlargement became depressed and developed elliptical cankers with vertical and horizontal slits, partially or completely girdling the affected trunk or branch. In advanced stages, the cankered surface however, became was black and brittle which remained studded with numerous black fissures. The fungus isolated from stem bark canker produced olivaceous to violaceous black fungal colonies with dense aerial mycelium. The hyphae were smooth, thick walled, septate and dark brown in colour. The pycnidia formed only in presence of light were globose to sub-globose distributed uniformally over the culture medium. The conidiogenous cells were smooth, hyaline, sub-cylindrical, swollen at the base, producing single apical conidium. The conidia were smooth, thin walled, hyaline, unicellular, fusoid to ellipsoidal with an obtuse apex and truncate or sub-truncate to rounded base. Based on morphological characters both on host as well as in culture, symptom expression and pathogenicity tests, the fungus causing the disease was identified as Fusicoccum aesculi Corda.

Pages: 2343-2352  |  975 Views  579 Downloads

Download (1246KB)