ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Benomyl resistance of Colletotrichum species associated with mango and rambutan fruit rots in Thailand.

Farungsang, U.; Farungsang, N.; Sangchote, S.;

Development of postharvest handling technology for tropical tree fruits: a workshop held in Bangkok, Thailand, 16-18 July 1992. Year: 1994 Pages: 45-50 Ref: 6 ref.

1994

บทคัดย่อ

ABSTRACT

Mature fruits of rambutan and mango were collected randomly from various locations in Thailand: rambutan from the east (Rayong, Chanthaburi and Trat) and south (Chumphon and Nakhon Si Thammarat); and mango from the central (Ratchaburi, Nakhon Pathom, Chon Buri and Nakhon Ratchas ima). The fruits were incubated to assess the incidence of fruit decay and Colletotrichum spp. were isolated from the disease lesions. The benomyl tolerance of these isolates was determined by examining their growth on potato dextrose agar (PDA) supplemented with benomyl (PDA+B), at concn of 0, 0.1, 1.0, 5.0 and 10.0 p.p.m. Thirty-one isolates from mango and 36 (east) and 42 (south) isolates from rambutan were tested. Tolerance of benomyl was rated at 3 levels: strongly tolerant, moderately tolerant and sensitive. The differences in colonial characteristics were noted in isolates that grew on PDA+B, but the abnormalities were absent in the strongly tolerant isolates. Of the rambutan isolates from the east, 3 were strongl

y tolerant and 1 isolate moderately tolerant of benomyl at 10.0 p.p.m. Of the rambutan isolates from the south, 2 were strongly tolerant and 1 was moderately tolerant of benomyl at 1.0 p.p.m. Similarly, 4 isolates from mango were moderately tolerant of benomyl at 1.0 p.p.m. This is the first report of tolerance of benomyl of field-collected isolates of Colletotrichum spp. in Thailand. Their occurrence in relation to the field spraying of benomyl is discussed.