Spatial and temporal distribution of pink fungus Corticium salmonicolor in Lanete, Jackfruit and Indian prickly ash plantations

Pink disease, caused by pink fungus (Corticium salmonicolor) attacks several woody plant species especially in the tropics. This fungus infects stem, branches, and twigs of the trees which eventually wilted and died. Pink disease was first reported in Wanagama Educational Forest Gunungkidul’s genetic trial of Lanete (Wrightia pubescens), Jackfruit (Artocarpus heterophyllus), and Indian Prickly Ash (Zanthoxylum rhetsa) late 2015. Based on preliminary survey, pink fungus was able to grow rapidly during rainy season. In order to manage the pink disease in the educational forest, a research was conducted with objectives as follows, 1) evaluate the number of infected trees and development of pink disease; 2) evaluate pink disease distribution pattern in the genetic trials stands of W. pubescens, A. heterophyllus, and Z. rhetsa. Data were collected in an agroforestry based genetic trials stands in Compartment 17 of Wanagama, Gunungkidul once every two weeks during the rainy seasons (February-April 2017). Temporal score-based symptoms development were observed to calculate disease incidence and severity using modified Chester’s formula. The increased number of symptomatic trees were mapped with GPS (Garmin76CSx) and ArcGIS sofware. The results show that the number of symptomatic trees were increased during 6 weeks of observations 204.5% % in W. pubescens, 200% in A. heterophyllus, and 250% in Z. rhetsa. The stem diameter of the trees were not correlated to either the symptoms development or the stages of the disease. Meanwhile, precipitation were strongly correlated to the increased number of trees with pink disease. The diseases’ spatial distribution pattern in W. pubescens and A. heterophyllus were clustered, but random pattern found only in Z. rhetsa. Nevertheless, the overall disease’s pattern was clustered. In order to prevent the spread of the pink fungus especially during the rainy season, intensive disease monitoring were needed so the development and spread of the pink disease within and between trees species could be closely monitored and prevented.