ABA Increases Susceptibility of Pepper Fruits to Infection of Anthracnose by Collectotrichum acutatum

Hwang, Soo Kyeong; Kim, Joo Hyung; Kim, Young Ho; Kim, Heung Tae

The Plant Pathology Journal 2008;24(4):400-406.
Published online December 31, 2008.

ABA Increases Susceptibility of Pepper Fruits to Infection of Anthracnose by Collectotrichum acutatum

Soo Kyeong Hwang, Joo Hyung Kim, Young Ho Kim, Heung Tae Kim

Abstract

To examine the relationship between plant hormones and the development of pepper anthracnose, we investigated the effects of several plant hormones on the progression of disease symptoms. Of the five plant hormones examined, abscisic acid (ABA) increased the lesion length and disease incidence on detached fruits of Capsicum annuum cv. Nokkwang. The simultaneous application of ABA with inoculation of Colletotrichum acutatum JC24 resulted in increased lesion length, depending the concentration of ABA applied. Additionally, application of ABA caused the development of pepper anthracnose in fruits of Capsicum baccatum cvs. PBC80 and PBC81, which were previously resistant to the disease. Furthermore, ABA administration rendered increased pathogenicity of other isolates of C. acutatum BAC02063, PECH10, and TCBNU3 obtained from the Chinese matrimony vine, peach, and tea tree, respectively. Our data suggest that exogenous ABA may result in the suppression of defense mechanisms of pepper fruits against anthracnose, which leads to a change in the susceptibility of pepper fruits and the development of pepper anthracnose.

Key Words: abscisic acid, Colletotrichum acutatum, pepper anthracnose