Almost all previous reports on plant esterase(EST)isoenzyme analysis appeared to have ac-cepted that the relative staining strength(RSS)ofelectrophoretical bands represented the relative ac-tivities and contents of th...Almost all previous reports on plant esterase(EST)isoenzyme analysis appeared to have ac-cepted that the relative staining strength(RSS)ofelectrophoretical bands represented the relative ac-tivities and contents of the correspondingisoenzymes.Nevertheless,we found in studyingthat the RSS changed with different staining展开更多
EST isozymes are one of the frequently used biochemical markers in genetic analysis of fungi. and the staining is an important process in electrophoresis analysis of studying Est.The effects were compared ainong diff...EST isozymes are one of the frequently used biochemical markers in genetic analysis of fungi. and the staining is an important process in electrophoresis analysis of studying Est.The effects were compared ainong different stain recipes for Est of 3 kinds of fungi-Lentinus edodes. Pleurotus sapidus. Phellinus igriarius and 2 kinds of plants-Populus sp and Brassica chinensis. Of the four kinds of Est staining recipes tested.the recipe α-acetic acid-naphther showed the best effect.and followed by β-aceticacid-naphther, semicontent α-aceticacid-naphther and α+β-aceticacidnathpher.展开更多
Copper is an important ingredient in fungicides,which are used for many economic plants.However,there is concern about the side-effects of copper-based fungicides due to their potential to affect beneficial mites.The ...Copper is an important ingredient in fungicides,which are used for many economic plants.However,there is concern about the side-effects of copper-based fungicides due to their potential to affect beneficial mites.The purpose of the present paper was to investigate the effects of copper on the development of the fruit fly,Drosophila melanogaster.It was found that higher doses of copper significantly prolonged the developmental time of the fruit flies,especially during the larval stages.When 320 mg L-1 copper-contaminated food was used,most of the larvae died when they were small and before the pupal stage.The protein contents and esterase isozymes extracted from the larvae changed according to the doses of copper.The small-molecular-weight protein bands gradually became weaker or were lost as the copper levels increased.However,low doses of copper stimulated a stronger expression of a few proteins.These results indicate that low doses of copper generally have no lethal effects on D.melanogaster because a specific group of genes,which encode specific proteins,are probably activated in order to withstand the onslaught of stressful conditions.At high doses of copper in food(e.g.320 mg L-1),fly development and viability are significantly affected.展开更多
The rice leaf folder (RLF), Cnaphalocrocis medinalis (Guenee) (lnsecta: Lepidoptera: Pyralidae), is an important pest, widely distributed in many rice growing areas of Asia. The over-use of broad-spectrum chem...The rice leaf folder (RLF), Cnaphalocrocis medinalis (Guenee) (lnsecta: Lepidoptera: Pyralidae), is an important pest, widely distributed in many rice growing areas of Asia. The over-use of broad-spectrum chemical insecticides has been cited as a major cause of outbreaks of C. medinalis as excessive spraying of insecticide disrupts natural biological control insecticides still remain the major control tactics against leaf folder. Carbofuran and fenthion, bendiocarb, acephate, carbosulfan, quinolphos, monocrotophos, phosphamidon and fenvalerate are the common ones used against rice leaf folder. Genetically, modified rice lines expressing B. thuringiensis insecticidal crystal proteins produced are highly tolerant to leidopteran pests. Though economic and environmental benefits of GM crops is well established, the matter of concern is the possibility of target insect pest developing resistance to this B. thuringiensis insecticidal toxins, evident from many laboratory and field experiments against many insect pests. The involvement of GSH S-transferase, carboxylesterase, and microsomal monooxygenase in insecticide resistance has been reported in insecticide-resistant strains of many insect species. Hence, the present study was taken up to monitor for cross resistance between B. thuringiensis cry toxins and synthetic insecticides in larvae of leaf folder as it is mediated by carboxylesterase titre and other enzymes by bioassay for two selected rice leaf folder field populations at the Entomology division of Directorate of Rice Research which showed 2-fold resistance ratio. Qualitative and quantitative changes of carboxylesterase (CarE) and glutathione-s-transferase (GST's) were worked out with midguts extracts of the two C. medinalis populations in the presence of a-napthyl acetate and chlorodi-nitro benzene substrates.展开更多
The vertical slab polyacrylamide gel electrophoretic technique is used to examine the esterase isozyme of four species (Hemiptera: Coreidae), the analysis has revealed that esterase zymogram can be divided into four z...The vertical slab polyacrylamide gel electrophoretic technique is used to examine the esterase isozyme of four species (Hemiptera: Coreidae), the analysis has revealed that esterase zymogram can be divided into four zones. Esterase zymogram of intergeneric species show distinct difference, while some intrageneric common features are discovered. The clustering analysis shows that the taxonomic status of 4 species, and sex variance is bigger than individuals and is smaller than species.展开更多
文摘Almost all previous reports on plant esterase(EST)isoenzyme analysis appeared to have ac-cepted that the relative staining strength(RSS)ofelectrophoretical bands represented the relative ac-tivities and contents of the correspondingisoenzymes.Nevertheless,we found in studyingthat the RSS changed with different staining
文摘EST isozymes are one of the frequently used biochemical markers in genetic analysis of fungi. and the staining is an important process in electrophoresis analysis of studying Est.The effects were compared ainong different stain recipes for Est of 3 kinds of fungi-Lentinus edodes. Pleurotus sapidus. Phellinus igriarius and 2 kinds of plants-Populus sp and Brassica chinensis. Of the four kinds of Est staining recipes tested.the recipe α-acetic acid-naphther showed the best effect.and followed by β-aceticacid-naphther, semicontent α-aceticacid-naphther and α+β-aceticacidnathpher.
基金supported by the National Natural Science foundation of China (No.30300035)by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry[No. (2004)527].
文摘Copper is an important ingredient in fungicides,which are used for many economic plants.However,there is concern about the side-effects of copper-based fungicides due to their potential to affect beneficial mites.The purpose of the present paper was to investigate the effects of copper on the development of the fruit fly,Drosophila melanogaster.It was found that higher doses of copper significantly prolonged the developmental time of the fruit flies,especially during the larval stages.When 320 mg L-1 copper-contaminated food was used,most of the larvae died when they were small and before the pupal stage.The protein contents and esterase isozymes extracted from the larvae changed according to the doses of copper.The small-molecular-weight protein bands gradually became weaker or were lost as the copper levels increased.However,low doses of copper stimulated a stronger expression of a few proteins.These results indicate that low doses of copper generally have no lethal effects on D.melanogaster because a specific group of genes,which encode specific proteins,are probably activated in order to withstand the onslaught of stressful conditions.At high doses of copper in food(e.g.320 mg L-1),fly development and viability are significantly affected.
文摘The rice leaf folder (RLF), Cnaphalocrocis medinalis (Guenee) (lnsecta: Lepidoptera: Pyralidae), is an important pest, widely distributed in many rice growing areas of Asia. The over-use of broad-spectrum chemical insecticides has been cited as a major cause of outbreaks of C. medinalis as excessive spraying of insecticide disrupts natural biological control insecticides still remain the major control tactics against leaf folder. Carbofuran and fenthion, bendiocarb, acephate, carbosulfan, quinolphos, monocrotophos, phosphamidon and fenvalerate are the common ones used against rice leaf folder. Genetically, modified rice lines expressing B. thuringiensis insecticidal crystal proteins produced are highly tolerant to leidopteran pests. Though economic and environmental benefits of GM crops is well established, the matter of concern is the possibility of target insect pest developing resistance to this B. thuringiensis insecticidal toxins, evident from many laboratory and field experiments against many insect pests. The involvement of GSH S-transferase, carboxylesterase, and microsomal monooxygenase in insecticide resistance has been reported in insecticide-resistant strains of many insect species. Hence, the present study was taken up to monitor for cross resistance between B. thuringiensis cry toxins and synthetic insecticides in larvae of leaf folder as it is mediated by carboxylesterase titre and other enzymes by bioassay for two selected rice leaf folder field populations at the Entomology division of Directorate of Rice Research which showed 2-fold resistance ratio. Qualitative and quantitative changes of carboxylesterase (CarE) and glutathione-s-transferase (GST's) were worked out with midguts extracts of the two C. medinalis populations in the presence of a-napthyl acetate and chlorodi-nitro benzene substrates.
文摘The vertical slab polyacrylamide gel electrophoretic technique is used to examine the esterase isozyme of four species (Hemiptera: Coreidae), the analysis has revealed that esterase zymogram can be divided into four zones. Esterase zymogram of intergeneric species show distinct difference, while some intrageneric common features are discovered. The clustering analysis shows that the taxonomic status of 4 species, and sex variance is bigger than individuals and is smaller than species.