Screening of effective pesticides to control rubber tree leaf fall disease (LFD) caused by Neopestalotiopsis and Colletotrichum fungi in Indonesia.

Abstract

In recent years, the stable supply of natural rubber has been threatened by a new leaf fall disease (LFD) caused by filamentous fungi. We screened pesticides to control the growth of Neopestalotiopsis sp. and Colletotrichum sp., which are considered to be the causal agents of LFD in rubber trees. We identified two effective pesticides, Quinondo 80% WP and Topsin M WP. When these two candidate pesticides were used in combination at 10 ppm each, there was enhanced inhibition of growth of both fungal species. Furthermore, the use of Quinondo 80% WP was shown to suppress the development of necrotic lesions caused by Neopestalotiopsis in rubber seedlings. These results suggest that Quinondo 80% WP is effective in controlling the spread of damage caused by LFD infection in rubber trees, and further verification of the concentration and method of application is needed to further demonstrate its effectiveness.