| Summary: | 碩士 === 國立中興大學 === 植物病理學系 === 85 === Methods for nematicide-resistance detection had been developed
by LD50 testingof Probit analysis in insecticide researchs.
IC50 of nematodes to nonfumigantnematicides carbofuran and
fenamiphos was evaluated by touch-response method.The result
showed that IC50 of Carbofuran and Fenamiphos to
Meloidogyneincognita, Pratylenchus coffeae, and Aphelenchoides
besseyi are 24.04 and3.59, 9.88 and 3.47, 32.31 and 9.5
respectively. Differential sensitivity of2nd stage juveniles
of different isolates of root knot nematode to carbofuranand
fenamiphos at IC50 of M. incognita was detected. Generally, M.
arenariaand M. graminicola were most sensitive and less
recovery after removal ofnematicides. Paralysis rate of M.
arenaria to fenamiphos and carbofuran was0.927and 0.972,
0.725 and 0.804; M. graminicola was 0.928 and
0.881,0.904-0.151; M. hapla was 0.449 and 0.192, 0.405 and
0.151; M. incognita was0.554 and 0.474, 0.488 and 0.208; M.
incognita was 0.802 and 0.714, 0.526 and0.152. Chemotaxis of A.
besseyi to Saintpanlia ionanntha was inhibited at 0.1μ g/ml of
these two nematicides and the reproduction at 1 μ g/ml was
reducedto half. Nematode was localized on soil surface by two
layer of cellophane todetect nematicide efficiency in planting
media. The efficiency of nematicidewas reduced by organic
matter or soil amendements. And the efficiency ofcarbofuran
was reduced to zero in peat moss or in 0.05% LT
mixtureamended-soil. Nematicide transportation in root system
was detected usingexcised root of Ipomoea reptans growing
in the biocompartment apparatus.Oxamyl reduced nematode
infection more than 35%. Ipomoea reptans stempesticides
injection and foliar nematode bioassay provided a
conveniecntmethod to detect chemicals transportable in
phloem. Oxamyl, fenamiphos,carbofuran, marshel, and mocap were
bipolarly trasported. Maeshel, methomyl,and tamaron were only
transported upward. Foliar spray of 100mg of oxamyl
toMomoridica charantia or injected 100 μ g into Ipomoea
reptans stem protectedroot from M. incognita for at least
10days. 0.05% Triton- X100 incerasedefficiency of fenamiphos
and carbofuran at least 20% in nematode mortality.The
efficiency of fenamiphos and carbofuran cooperative appliaction
was higherthan only one nematicide.
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