الفهرس 
Entomopathogenic nematode cultureOnly 14 pages are availabe for public view
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Abstract
Currently, nematologists involved in the biological control of
nematodes have adopted two main strategies: the manipulation of
indigenous natural enemies in soil by using organic matter, and the
introduction of selected agents as inundative treatments. Some organic
materials contain nematoxic chemicals and when these materials are
used as soil amendments, the nematicidal principle is released into soil
and is directly responsible for the suppression of nematode
populations. Moreover, some microbial antagonists by themselves
release toxic substances.
The present investigation tackeled the problem of the
biological control of root-knot nematode, Meloidogyne incognita,
using introduced microbial antagonists in an alien soil environment,
and incorporating plant materials of different C/N ratio in soil. The
effect of these two components, viz., antagonists and plant materials,
was also studied on the soil-inhabiting entomopathogenic nematode,
Heterorhabditis bacterio-phora.
The efficacy of five microbial agents, Bacillus circulans, B.
megaterium, Serratia marcescens, Streptomyces sp., and Trichoderma
viride, were tested against the second juvenile stage (J2s) of M.
incognita (Mi), in the laboratory in cups, and in the screenhouse on
tomato seedlings in pots, and on the third juvenile (IJ3s) stage of H.
bacteriophora (Hb) in the laboratory in cups.
Chopped dried vegetative parts of marigold, Tagetes erecta
(C/N 39.4:1), sunn hemp, Crotalaria juncia (C/N 33.9:1), and clover,
Trifolium alexandrinum (C/N 20.2:1), rice straw, Oryza sativa (C/N
54.1:1), and sawdust were (C/N 122.3:1) singly and thoroughly mixed
with soil (1% w/w) as soil amendments. The experiments were
conducted in the laboratory and in the screenhouse.
(1) In the laboratory
(1-1) Microbes in broth culture (Mm), supernatants of broth cultures
free of microbes (S), and microbes in plain water (Mw) were
tested against juveniles at five dilutions (52.5x106, 26.2 x106.