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131.
Superoxide dismutase (SoDase) polymorphism in reference populations of potato cyst nematodes (PCN) was studied by isoelectric focusing and compared with the banding pattern obtained from 26 English field populations of PCN. Qualitative and quantitative differences were found between the reference populations: a band detected only in the G. rostochiensis Ro4 and Ro5 reference populations was found in four field populations of varying pathotype composition and two field populations of G. rostochiensis Rol possessed extra bands that were not detected in the other field populations. Analysis of the band differences showed little correlation between pathotype and banding pattern in the field populations. 相似文献
132.
133.
A test for discriminating between models 总被引:1,自引:0,他引:1
134.
W. D. ATKINSON 《Ecological Entomology》1981,6(4):339-344
Abstract. 1. Potential Drosophila breeding sites were collected from a fruit market, and the adults allowed to emerge from them.
2. D.immigrans and D.melanogaster were the species with the highest frequency of emergences from citrus fruit.
3. D.immigrans was especially associated with citrus fruits infected with Penicillium italicum or P.digitatum , two specialist moulds of citrus. D.melanogaster was more often found in uninfected fruit.
4. In the laboratory D.immigrans larvae survived better than D.melanogaster larvae on Penicillium-infected citrus fruit.
5. These adaptations suggest that D.immigrans may have originally evolved as a citrus specialist, becoming a domestic species as these fruits were exploited commercially. 相似文献
2. D.immigrans and D.melanogaster were the species with the highest frequency of emergences from citrus fruit.
3. D.immigrans was especially associated with citrus fruits infected with Penicillium italicum or P.digitatum , two specialist moulds of citrus. D.melanogaster was more often found in uninfected fruit.
4. In the laboratory D.immigrans larvae survived better than D.melanogaster larvae on Penicillium-infected citrus fruit.
5. These adaptations suggest that D.immigrans may have originally evolved as a citrus specialist, becoming a domestic species as these fruits were exploited commercially. 相似文献
135.
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137.
Two inhibitors of hatching in Globodera rostochiensis, ruthenium red and lanthanum, have been shown to bind to the eggshell using the techniques of microdensitometry for ruthenium red and X-ray microanalysis for lanthanum. Neither inhibitor penetrated or adhered to unhatched or hatched viable juveniles. Scatchard analysis for binding of lanthanum and ruthenium red to eggshells gave dissociation constants (K) of KLa 32.5 ± 14.0 μM and KRured 33.5 ± 5.0 μM respectively. Both values are within the 95% fiducial limits of those shown to cause 50% inhibition of hatch in previous work. Pretreatment with sodium hypochlorite separated an outer part of the eggshell from an inner region which exclusively bound ruthenium red. It is the inner lipoprotein layer that is believed to include the membranes controlling the permeability of the tylenchid eggshell. The rate of binding of ruthenium red was similar for intact and isolated eggshells with 50% binding occurring after 6.11 ± 0.91 min and 4.95 ± 2.38 min but the latter gave a significantly higher maximum binding suggesting that rupture of the eggshells made available additional binding sites on their inner surface. The binding of ruthenium red to the eggshells was pH dependant over most of the range pH 2.8–8.5 with 50% binding, given with its standard deviation, occurring at pH 5.75 ± 0.85. Competitive binding of lanthanum influenced the binding of ruthenium red to the eggshells from which Scatchard analysis gave Kla of 176 ± 79 μM. Similarly, calcium influenced the binding but this caused a biphasic plot with high and low affinity binding sites of K“ca of 0.423 ± 1.16 μm and K‘ca of 1078 ± 462 μM. The existence of a high affinity site for calcium that also binds ruthenium red, suggests that the eggshell membrane includes a calcium binding glycoprotein as found in some other receptor mechanisms. 相似文献
138.
139.
THE sodium and potassium-dependent water-soluble transport ATPase which is described here has been shown to be homogeneous by disc gel electrophoresis and stable at 0° C, but more active than previous preparations1,2. The enzyme is probably a trimer with monomers which retain ouabain-insensitive ATPase activity and which can dissociate further into four subunits. This multi-subunit system provides a basis for accounting for the complex kinetics of the transport ATPase3–6. 相似文献
140.