To screen out the rapeseed(Brassica napus) combinations that are suitable for the production of both oilseed and vegetable, we carried out a field experiment for 11 new combinations(hybrids) of rapeseed and then perfo...To screen out the rapeseed(Brassica napus) combinations that are suitable for the production of both oilseed and vegetable, we carried out a field experiment for 11 new combinations(hybrids) of rapeseed and then performed grey relation analysis and cluster analysis on 12 traits including the yield and quality of young stem,seed yield, and several agronomic traits after harvesting of young stem. The results showed that A11, A7, and A4 had higher main stalk yield than other combinations.The young stem/leaf ratios of A11, A5, A7, A4, A3, and A1 were in line with the quality requirements for young stem commodity. The soluble sugar content of A2,A8, and A10 was higher than that of CK(Fengyou 737), and the seed yields of A4,A3, A2, A1, A5, and A6 were higher than that of CK. The 11 rapeseed combinations were classified into 3 grades by grey relation analysis and cluster analysis. Two combinations, A4(Y20A×95C4R) and A11(3194A×09-5R), showed the weighted relation degrees higher than 0.95, which were clustered into grade I by cluster analysis. They had good agronomic traits and good performance as both oilseed and vegetable. A8, A5, A3, A7, A2, A10, A6, and A1 were clustered into grade Ⅱ and A9 into grade Ⅲ. In this study, the oilseed and vegetable dual-purpose rapeseed combinations were screened out based on grey relation analysis and cluster analysis,which can provide reference for the breeding of oilseed and vegetable dual-purpose rapeseed combinations.展开更多
With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RN...With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RNAi silencing the expression of genes related to pollen development, early degradation of tapetum callose leading to male sterility. Male sterile transgenic plants can be obtained through genetic transformation with related genes destroying or interfering with pollen or anther development. Male sterile cauliflower, tomato, cabbage, etc. have been developed in this way, and some begin to be used to produce hybrid seed. Appling some techniques can also maintain and restore the male sterility. These related researches will effectively promote the heterosis utilization and the development of crop breeding. This paper mainly presents their principles and applications in vegetable crops.展开更多
The East Calcutta Wetlands （West Bengal, India） receive the urban sewage of Calcutta. Part of the wetlands is also used as a landfill. A sizeable peri-urban population （some resident, some commuting） are engaged i...The East Calcutta Wetlands （West Bengal, India） receive the urban sewage of Calcutta. Part of the wetlands is also used as a landfill. A sizeable peri-urban population （some resident, some commuting） are engaged in the area in fishing, agriculture, vegetable farming and garbage recycling activities. The importance of the wetlands is that they maintain the food chain and ecological balance, absorb pollution, treat sewage, and sustain fishes. This study of the Wetlands aimed to： [1） identify the local livelihoods based on use of urban wastewater; （2） estimate the value of direct benefits derived by these stakeholders from its use; and （3） estimate the environmental impact of East Calcutta Wetlands on stakeholders. Three main livelihood options using wastewater were identified： fisheries, paddy cultivation and garbage farming. Use of urban wastewater provides significant income for the poor residing in the wetlands. However adverse environmental and health impacts are occurring as urban expansion is allowed without an understanding of how to preserve the ecological, environmental and economic benefits of the sewage-fed aquaculture system. Focused and directed developmental programs must be devised to protect the East Calcutta Wetlands while improving the living standards of the people residing there.展开更多
文摘To screen out the rapeseed(Brassica napus) combinations that are suitable for the production of both oilseed and vegetable, we carried out a field experiment for 11 new combinations(hybrids) of rapeseed and then performed grey relation analysis and cluster analysis on 12 traits including the yield and quality of young stem,seed yield, and several agronomic traits after harvesting of young stem. The results showed that A11, A7, and A4 had higher main stalk yield than other combinations.The young stem/leaf ratios of A11, A5, A7, A4, A3, and A1 were in line with the quality requirements for young stem commodity. The soluble sugar content of A2,A8, and A10 was higher than that of CK(Fengyou 737), and the seed yields of A4,A3, A2, A1, A5, and A6 were higher than that of CK. The 11 rapeseed combinations were classified into 3 grades by grey relation analysis and cluster analysis. Two combinations, A4(Y20A×95C4R) and A11(3194A×09-5R), showed the weighted relation degrees higher than 0.95, which were clustered into grade I by cluster analysis. They had good agronomic traits and good performance as both oilseed and vegetable. A8, A5, A3, A7, A2, A10, A6, and A1 were clustered into grade Ⅱ and A9 into grade Ⅲ. In this study, the oilseed and vegetable dual-purpose rapeseed combinations were screened out based on grey relation analysis and cluster analysis,which can provide reference for the breeding of oilseed and vegetable dual-purpose rapeseed combinations.
文摘With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RNAi silencing the expression of genes related to pollen development, early degradation of tapetum callose leading to male sterility. Male sterile transgenic plants can be obtained through genetic transformation with related genes destroying or interfering with pollen or anther development. Male sterile cauliflower, tomato, cabbage, etc. have been developed in this way, and some begin to be used to produce hybrid seed. Appling some techniques can also maintain and restore the male sterility. These related researches will effectively promote the heterosis utilization and the development of crop breeding. This paper mainly presents their principles and applications in vegetable crops.
文摘The East Calcutta Wetlands （West Bengal, India） receive the urban sewage of Calcutta. Part of the wetlands is also used as a landfill. A sizeable peri-urban population （some resident, some commuting） are engaged in the area in fishing, agriculture, vegetable farming and garbage recycling activities. The importance of the wetlands is that they maintain the food chain and ecological balance, absorb pollution, treat sewage, and sustain fishes. This study of the Wetlands aimed to： [1） identify the local livelihoods based on use of urban wastewater; （2） estimate the value of direct benefits derived by these stakeholders from its use; and （3） estimate the environmental impact of East Calcutta Wetlands on stakeholders. Three main livelihood options using wastewater were identified： fisheries, paddy cultivation and garbage farming. Use of urban wastewater provides significant income for the poor residing in the wetlands. However adverse environmental and health impacts are occurring as urban expansion is allowed without an understanding of how to preserve the ecological, environmental and economic benefits of the sewage-fed aquaculture system. Focused and directed developmental programs must be devised to protect the East Calcutta Wetlands while improving the living standards of the people residing there.
