ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Infection of flower and vegetative tissues of citrus by Colletotrichum acutatum and C. gloeosporioides.

Zulfiqar, M.; Brlansky, R. H.; Timmer, L. W.;

Mycologia Year: 1996 Vol: 88 Issue: 1 Pages: 121-128 Ref: 21 ref.

1996

บทคัดย่อ

C. acutatum caused postbloom fruit drop of citrus, whereas C. gloeosporioides [Glomerella cingulata] caused postharvest anthracnose on fruit but did not affect healthy leaf or flower tissues. Conidia of C. acutatum germinated and hyphae grew profusely on the surface of petals and penetrated without forming appressoria. This species developed abundant intercellular hyphae in 48 h and produced acervuli on the petal surface in 5 d. Conidia of G. cingulata germinated and grew to a limited extent on the surface of petals but did not penetrate tissues until petals had become senescent. On the leaf surface, conidia of both species germinated to produce appressoria. The appressoria of C. acutatum, but not of G. cingulata, germinated to form hyphae and conidia under moist conditions in response to applications of flower extracts but did not form acervuli. C. acutatum produced infection pegs and quiescent infections on leaves as did G. cingulata as indicated by the presence of openings at the point of con

tact of the appressoria with the leaf surface, and by reisolation of both strains from surface-sterilized leaves. Under lab. conditions, C. acutatum colonized senescent leaves and produced abundant acervuli on the surface as did G. cingulata. C. acutatum appeared to overwinter primarily as appressoria on living leaves rather than in colonized dead tissues like G. cingulata.