Affiliation:
1. Department of Plant Pathology, The Pennsylvania State University, University Park, Pennsylvania 16802
Abstract
ABSTRACT
We used randomly amplified polymorphic DNA (RAPD)-PCR to estimate genetic variation among isolates of
Trichoderma
associated with green mold on the cultivated mushroom
Agaricus bisporus
. Of 83 isolates examined, 66 were sampled during the recent green mold epidemic, while the remaining 17 isolates were collected just prior to the epidemic and date back to the 1950s.
Trichoderma harzianum
biotype 4 was identified by RAPD analysis as the cause of almost 90% of the epidemic-related episodes of green mold occurring in the major commercial mushroom-growing region in North America. Biotype 4 was more closely allied to
T. harzianum
biotype 2, the predominant pathogenic genotype in Europe, than to the less pathogenic biotype 1 and
Trichoderma atroviride
(formerly
T. harzianum
biotype 3). No variation in the RAPD patterns was observed among the isolates within biotype 2 or 4, suggesting that the two pathogenic biotypes were populations containing single clones. Considerable genetic variation, however, was noted among isolates of biotype 1 and
T. atroviride
from Europe. Biotype 4 was not represented by the preepidemic isolates of
Trichoderma
as determined by RAPD markers and PCR amplification of an arbitrary DNA sequence unique to the genomes of biotypes 2 and 4. Our findings suggest that the onset of the green mold epidemic in North America resulted from the recent introduction of a highly virulent genotype of the pathogen into cultivated mushrooms.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Cited by
20 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献