Maria Jaime, M.Sc. Student (1999 - 2001)
Biological control of Allium white rot caused
by Sclerotium cepivorum Berk, in onions on organic soil
Email to Maria Jaime (currently
Ph.D. student at the University of Toronto, Mississauga Campus)
Abstract of talk presented at CPS 2001 in London Ontario. Can. J. Plant
Interaction between the vesicular arbuscular mycorrhizal fungus, Glomus
intraradices and Sclerotium cepivorum, white rot in onions.
M.D.L.A. Jaime1 , T. Hsiang2, M.R. McDonald1.
1Dept. Plant Agriculture,2Dept. Env. Biol., Univ.
Guelph. Guelph, ON. Canada N1G2W1. Studies were conducted to assess
the potential of the vesicular arbuscular mycorrhizal fungus, Glomus intraradices,
as a biological control of white rot caused by Sclerotium cepivorum
Berk. Onion plants were seeded in the greenhouse in the medium PROMIX PGX®
with the commercial formulation, MIKRO-VAM® incorporated at 1 g/plug
or in PROMIX PGX® with MYCORISE® 1000 or with MYCORISE® 255
. This allowed for root colonization before the onions were transplanted.
Onions were transplanted 6 - 7 weeks after seeding, into plots in two fields
of organic soil naturally infested with S. cepivorum and at a site
where S. cepivorum was not present. Disease incidence, extent of
root colonization, and fresh and dry weight were recorded. Beneficial effects
were observed in onions plants grown in MIKRO-VAM® and PROMIX PGX®
with MYCORISE® 1000 at sites where white rot was present. Disease incidence
at harvest was reduced by 31 to 49%. No differences in yield were found
among treatments at the site that was free of white rot.