Identification of the causal agent of gummosis stem rot disease on Jackfruit (Artocarpus heterophyllus) in Can Tho City, Viet Nam

Abstract

Based on the results of surveys conducted in jackfruit orchards, sample collection, and isolation of bacteria from

typical infected specimens over a two-year period in Hau Giang (formerly, now Can Tho City), as well as artificial

inoculation results on 3-4-year-old jackfruit trunks, the bacterium Pectobacterium aroidearum has been identified as the

causal agent of stem rot and gummosis in jackfruit trees. Symptoms appear year-round but develop rapidly during the

rainy season, with a damage rate reaching up to 50.93%. The disease is most severe in August and September, with

infection rates in orchards ranging from 66.67% to 73.33%. Pectobacterium aroidearum is motile, unable to grow in a

5% NaCl environment, and tests negative for both nitrate reduction and catalase reactions.