Distribution and Etiology of Gummosis Syndrome Associated with Apricot Fruit Trees of Gilgit-Baltistan, Pakistan

Abstract

Gummosis syndrome is a serious disease of apricot trees in Gilgit Baltistan (GB), Pakistan. The symptoms of gummosis syndrome on branches, twigs, and the trunk of apricot trees include oozing of a gummy or resinous material, lesions or cankers, bark discoloration, and the disintegration of bark integrity. The disease can weaken branches and twigs, making them more susceptible to breakage. In severe cases, affected branches can die back. In this study, we investigated the fungal species associated with gummosis syndrome in apricots across four districts in GB: Nagar, Hunza, Gilgit, and Ghizer. We recovered a total of 40 isolates from different locations of above four districts, and the most frequently isolated fungal species was Botryodiplodia theobromae. Fusarium solani was also isolated from several locations, and Neoscytalidium spp. were isolated from a few locations in Nagar and Hunza. The spatial distribution of gummosis syndrome in apricots in GB is not uniform. The disease is more prevalent in the northern and western parts of GB, and in areas with higher elevations and cooler temperatures. The Nagar district is the most affected by gummosis syndrome, followed by Ghizer District. Our findings suggest that Botryodiplodia theobromae is the major fungal pathogen associated with gummosis syndrome in apricots in GB. Fusarium solani and Neoscytalidium spp. may also play a role in the disease. The spatial distribution of gummosis syndrome in GB suggests that environmental factors, such as elevation and temperature, may contribute to the disease. Further research is needed to develop effective control measures for gummosis syndrome in apricots in GB. This research should focus on identifying resistant apricot varieties, developing new and more effective fungicides, and developing integrated pest management (IPM) programs.