On the MS medium supplemented with 2 ppm 2,4-D,calli were induced after 4-6weeks from the petioles of an American celery plant （Apium graveolens var.Dulce pers.cv.Florida）.Suspension culture was started from the cal...On the MS medium supplemented with 2 ppm 2,4-D,calli were induced after 4-6weeks from the petioles of an American celery plant （Apium graveolens var.Dulce pers.cv.Florida）.Suspension culture was started from the calli in a hormone-free liquid MS medium on agyratory shaker at 110 rpm,and kept at 26℃.To stimulate cell division and dedifferentiation,thesubcultures were conducted for 7 days each on the same medium.The liquid suspension containingsingle cells,cell aggregates,and somatic embryos in different stages were screened 2-3 weekslater and 1.0-1.5mm somatic embryos were obtained.These embryos were encapsulated withsodium alginate by dropping-bead method and solidified with 0.1mol CaCl<sub>2</sub>,.These synthetic seedsgerminated and developed well into seedlings in the sterilized vermiculite substrate.展开更多
A pot experiment and a sandy culture experiment grown with three vegetable crops of Chinese cabbage ( B. chinensis L., cv. Zao\|Shu 5), winter greens ( B.var.rosularis Tsen et Lee, cv. Shang\|Hai\|Qing) and cele...A pot experiment and a sandy culture experiment grown with three vegetable crops of Chinese cabbage ( B. chinensis L., cv. Zao\|Shu 5), winter greens ( B.var.rosularis Tsen et Lee, cv. Shang\|Hai\|Qing) and celery ( A.graveolens L. var. dulce DC., cv. Qing\|Qin) were conducted, respectively. The initial soil and four incubated soils with different extractable Cd (0.15, 0.89, 1.38, 1.84 and 2.30 mg Cd/kg soil) were used for the pot experiment. Five treatments were designed (0, 0.0625, 0.125, 0.250 and 0.500 mg Cd/L) in nutrient solution in the sandy culture experiment. Each treatment in pot and sandy culture experiments was trireplicated. The objectives of the study were to examine Cd accumulation in edible parts of selected vegetable crops, its correlation with Cd concentrations in vegetable garden soil or in nutrient solution, and evaluate the criteria of Cd pollution in vegetable garden soil and in nutrient solution based on the hygienic limit of Cd in vegetables. Cadmium concentrations in edible parts of the three selected vegetable crops were as follows: 0.01—0.15 mg/kg fresh weight for Chinese cabbage, 0.02—0.17 mg/kg fresh weight for winter greens, and 0.02—0.24 mg/kg fresh weight for celery in the pot experiment, and 0.1—0.4 mg/kg fresh weight for Chinese cabbage, 0.1—1.4 mg/kg fresh weight for winter greens, and 0.05—0.5 mg/kg fresh weight for celery in the pot experiment(except no\|Cd treatment). The order of the three test vegetable crops for cadmium accumulation in the edible parts was celery>winter greens>Chinese cabbage in both the pot experiment and the sandy culture experiment. Cadmium accumulation in edible parts or roots of the vegetable crops increased with increasing of cadmium concentration in the medium(soil or nutrient solution). And cadmium concentrations in edible parts of the test vegetable crops were significantly linearly related to the Cd levels in the growth media (soil and nutrient solution). Based on the regression equations established and the limit of cadmium concentration in vegetable products, the thresholds of Cd concentration in the growth medium evaluated was as follows: 0.5 mg/kg soil of extractable Cd for soil and 0.02 mg /L for nutrient solution. The high capacity for cadmium accumulation in the edible parts of different vegetable crops together with the absence of visual symptoms implies a potential danger for humans.展开更多
Objective:To determine the repellent properties of hexane,benzene,ethyl acetate,chloroform and methanol extract of Pithecellobium dulce(P.dulce)leaf and seed against Anopheles stephensi(An.stephensi).Methods:Repellent...Objective:To determine the repellent properties of hexane,benzene,ethyl acetate,chloroform and methanol extract of Pithecellobium dulce(P.dulce)leaf and seed against Anopheles stephensi(An.stephensi).Methods:Repellent activity assay was carried out in a net cage(45 cm×30 cm×25 cm)containing 100 blood starved female mosquitoes of An.stephensi.This assay was carried out in the laboratory conditions according to the WHO 2009 protocol.Plant crude extracts of P.dulce were applied at 1.0,2.5,and 5.0 mg/cm^(2) separately in the exposed fore arm of study subjects.Ethanol was used as the sole control.Results:In this study,the applied plant crude extracts were observed to protect against mosquito bites.There were no allergic reactions experienced by the study subjects.The repellent activity of the extract was dependent on the concentration of the extract.Among the tested solvents,the leaf and seed methanol extract showed the maximum efficacy.The highest concentration of 5.0 mg/cm^(2) leaf and seed methanol extract of P.dulce provided over 180 min and 150 min protection,respectively.Conclusions:Crude extracts of P.dulce exhibit the potential for controlling malaria vector mosquito An.stephensi.展开更多
Objective:To assess the larvicidal and ovicidal potential of the crude hexane,benzene,chloroform,ethyl acetate and methanol solvent extracts from the medicinal plant,Pithecellobium dulce(P.dulce)against filariasis vec...Objective:To assess the larvicidal and ovicidal potential of the crude hexane,benzene,chloroform,ethyl acetate and methanol solvent extracts from the medicinal plant,Pithecellobium dulce(P.dulce)against filariasis vector mosquito,Culex quinquefasciatus(Cx.quinquefasciatus).Methods:Twenty five early third instar larvae of Cx.quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol of W HO(2005).The larval mortality was observed after 24 h of treatment.The ovicidal activity was determined against Cx.quinquefasciatus mosquito eggs to various concentrations ranging from 100-750 mg/L under the laboratory conditions.Results:The methanol extract of the leaves and seed of P.dulce was the most effective against the larvae with LCs0 and LCgo values 164.12 mg/L,214.29 mg/L,289.34 mg/L and 410.18 mg/L being observed after 24 h of exposure.The efficacy of methanol was followed by that of the ethyl acetate,chloroform,benzene and hexane extracts.The mean percent hatchability of the egg rafts were observed after 48 h of treatment.About 100%mortality was observed at 500 mg/L for leaf and 750 mg/L for seed methanol extracts of P.dulce.Conclusions:From the results,it can be concluded that the larvicidal and ovicidal effect of P.dulce against Cx.quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.展开更多
文摘On the MS medium supplemented with 2 ppm 2,4-D,calli were induced after 4-6weeks from the petioles of an American celery plant （Apium graveolens var.Dulce pers.cv.Florida）.Suspension culture was started from the calli in a hormone-free liquid MS medium on agyratory shaker at 110 rpm,and kept at 26℃.To stimulate cell division and dedifferentiation,thesubcultures were conducted for 7 days each on the same medium.The liquid suspension containingsingle cells,cell aggregates,and somatic embryos in different stages were screened 2-3 weekslater and 1.0-1.5mm somatic embryos were obtained.These embryos were encapsulated withsodium alginate by dropping-bead method and solidified with 0.1mol CaCl<sub>2</sub>,.These synthetic seedsgerminated and developed well into seedlings in the sterilized vermiculite substrate.
文摘A pot experiment and a sandy culture experiment grown with three vegetable crops of Chinese cabbage ( B. chinensis L., cv. Zao\|Shu 5), winter greens ( B.var.rosularis Tsen et Lee, cv. Shang\|Hai\|Qing) and celery ( A.graveolens L. var. dulce DC., cv. Qing\|Qin) were conducted, respectively. The initial soil and four incubated soils with different extractable Cd (0.15, 0.89, 1.38, 1.84 and 2.30 mg Cd/kg soil) were used for the pot experiment. Five treatments were designed (0, 0.0625, 0.125, 0.250 and 0.500 mg Cd/L) in nutrient solution in the sandy culture experiment. Each treatment in pot and sandy culture experiments was trireplicated. The objectives of the study were to examine Cd accumulation in edible parts of selected vegetable crops, its correlation with Cd concentrations in vegetable garden soil or in nutrient solution, and evaluate the criteria of Cd pollution in vegetable garden soil and in nutrient solution based on the hygienic limit of Cd in vegetables. Cadmium concentrations in edible parts of the three selected vegetable crops were as follows: 0.01—0.15 mg/kg fresh weight for Chinese cabbage, 0.02—0.17 mg/kg fresh weight for winter greens, and 0.02—0.24 mg/kg fresh weight for celery in the pot experiment, and 0.1—0.4 mg/kg fresh weight for Chinese cabbage, 0.1—1.4 mg/kg fresh weight for winter greens, and 0.05—0.5 mg/kg fresh weight for celery in the pot experiment(except no\|Cd treatment). The order of the three test vegetable crops for cadmium accumulation in the edible parts was celery>winter greens>Chinese cabbage in both the pot experiment and the sandy culture experiment. Cadmium accumulation in edible parts or roots of the vegetable crops increased with increasing of cadmium concentration in the medium(soil or nutrient solution). And cadmium concentrations in edible parts of the test vegetable crops were significantly linearly related to the Cd levels in the growth media (soil and nutrient solution). Based on the regression equations established and the limit of cadmium concentration in vegetable products, the thresholds of Cd concentration in the growth medium evaluated was as follows: 0.5 mg/kg soil of extractable Cd for soil and 0.02 mg /L for nutrient solution. The high capacity for cadmium accumulation in the edible parts of different vegetable crops together with the absence of visual symptoms implies a potential danger for humans.
基金Suported by University Grants Commission,New Delhi,India(UGC)[F.No.39-646/2010(SR)].
文摘Objective:To determine the repellent properties of hexane,benzene,ethyl acetate,chloroform and methanol extract of Pithecellobium dulce(P.dulce)leaf and seed against Anopheles stephensi(An.stephensi).Methods:Repellent activity assay was carried out in a net cage(45 cm×30 cm×25 cm)containing 100 blood starved female mosquitoes of An.stephensi.This assay was carried out in the laboratory conditions according to the WHO 2009 protocol.Plant crude extracts of P.dulce were applied at 1.0,2.5,and 5.0 mg/cm^(2) separately in the exposed fore arm of study subjects.Ethanol was used as the sole control.Results:In this study,the applied plant crude extracts were observed to protect against mosquito bites.There were no allergic reactions experienced by the study subjects.The repellent activity of the extract was dependent on the concentration of the extract.Among the tested solvents,the leaf and seed methanol extract showed the maximum efficacy.The highest concentration of 5.0 mg/cm^(2) leaf and seed methanol extract of P.dulce provided over 180 min and 150 min protection,respectively.Conclusions:Crude extracts of P.dulce exhibit the potential for controlling malaria vector mosquito An.stephensi.
基金Supported by the University Grants Commission(UGC)[F.No.39-646/2010(SR)],New Delhi,India.
文摘Objective:To assess the larvicidal and ovicidal potential of the crude hexane,benzene,chloroform,ethyl acetate and methanol solvent extracts from the medicinal plant,Pithecellobium dulce(P.dulce)against filariasis vector mosquito,Culex quinquefasciatus(Cx.quinquefasciatus).Methods:Twenty five early third instar larvae of Cx.quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol of W HO(2005).The larval mortality was observed after 24 h of treatment.The ovicidal activity was determined against Cx.quinquefasciatus mosquito eggs to various concentrations ranging from 100-750 mg/L under the laboratory conditions.Results:The methanol extract of the leaves and seed of P.dulce was the most effective against the larvae with LCs0 and LCgo values 164.12 mg/L,214.29 mg/L,289.34 mg/L and 410.18 mg/L being observed after 24 h of exposure.The efficacy of methanol was followed by that of the ethyl acetate,chloroform,benzene and hexane extracts.The mean percent hatchability of the egg rafts were observed after 48 h of treatment.About 100%mortality was observed at 500 mg/L for leaf and 750 mg/L for seed methanol extracts of P.dulce.Conclusions:From the results,it can be concluded that the larvicidal and ovicidal effect of P.dulce against Cx.quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.
