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The tap and lateral roots of garden pea seedlings (cv.
Taichung 11)could be significantly injured and inhibited by
butachlor [2-chloro-2',6'-diethyl-N-(butoxymethyl)-acetanilide]
in the soil. Using gardenpea seedlings to bioassay the
toxicity of butachlor, the discolorationpercentage of their tap
roots was 13.73, 84.31 or 100 when the seedswere respectively
sown in soils pre-treated with 10, 50, or 100ppm ofbutachlor
for one month. Amendment of soil with 5%(w/w) spent
goldenmushroom compost(SGMC) was able to significantly
promote the growthand prevent roots of garden pea seedlings
from injury incited bybutachlor. Amendent of Tali or Chihu
soils with either Tsaohu orWufeng SGMC was effective in
gradually promoting the growth ofseedlings with increasing
of SGMC concentrations from 1 to 5%(w/w).The effectiveness of
Tsaohu SGMC was better than Wufeng SGMC. The sameeffect occured
in Tali and Chihu soils containing 50ppm butachlorafter
amendment of soil with Tsaochu or Wufeng SGMC. The SGMC was
ableto stimulate proliferation of microbial populations,
especially Mucorspp., Penicillium spp., Trichoderma spp.,
Streptomyces spp., andBacillus spp. in soil with or without
butachlor. Determining microbialactivity in soil containing
0-5%(w/w) SGMC or 0-1000ppm butachlor byspectrophotometric
determination of the hydrolysis of fluoresceindiacetate(
FDA). Hydrolysis was found to increase with increasing
thedoses of butachlor, excepted for 1000ppm, and concentrations
of SGMC.Amendment of infested or disinfested soil containing
50ppm butachlorwith non-sterilized SGMC could reduce 22% or
more injury severity oftap roots of garden pea compared to
amendment with sterilized SGMC.Amendment of soil with
F-101 microbial compost, sterilized SGMCcolonized by Mucor
sp.(F-101) for 7 days at 28 ℃, was the sameeffective in
alleviating root injury of garden pea seedlings
bybutachlor as amendment with non-sterilized SGMC.
Among manypredominant microorganisms, Mucor sp.(
F-101), Trichodermahamatum(F-104), T. aureoviride(F-108), T.
koningii(F-115), Penicilliumverrucosum Dierckx, var.
cyclopium(F-116), Streptomyces sp.(A-107),Streptomyces sp.(
A-112), and Bacillus brevis(B-109) were able todegrade
butachlor in amended soil, potato dextrose broth(PDB),
ornutrient broth(NB). Especially, Mucor sp.(F-101),
Trichodermahamatum(F-104), Trichoderma aureoviride(
F-108), Trichodermakoningii(F-115) and Penicillium
verrucosum var. cyclopium(F-116) werebetter than others in
ability to degrade butachlor. It was found thatthe residue of
butachlor markedly decreased with increment of
sporeconcentration when spore suspensions(0~5 × 10^8cfu/ml)
of Mucorsp.(F-101) were inoculated into sterilized soil and
PDB containing50ppm butachlor and incubated for 7 days.
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