Effect of fertilizer source （mineral fertilizer or organic manure） on photosynthetic pigments leaves content of four brassica vegetables （Pak choi, Kohlrabi, Cauliflower and Cabbage） was tested. Among treatments, ...Effect of fertilizer source （mineral fertilizer or organic manure） on photosynthetic pigments leaves content of four brassica vegetables （Pak choi, Kohlrabi, Cauliflower and Cabbage） was tested. Among treatments, cauliflower fertilized with chicken manure had the highest content of chlorophyll a and b （10.08 and 9.37 μm·g^-1）, while, pak choi had the lowest values （2.00 and 2.44 μm·g^-1） in non-fertilized plants. These differences in chlorophyll a and b content may have a great impact on photosynthetic rate and activity. Total carotenoids and total xanthophylls （lutein, zeaxanthin, antheraxanthin and violaxanthin） were the highest in cauliflower while the lowest was in pakchoi, β-carotene, on the other hand, was the highest percentage of total carotenoids （65.7%） in pak choi while Kohlrabi had the lowest percent （57.4%）. This high percentage offl-carotene of total carotenoids may compensate for lower content of chlorophylls and assist for efficient light harvesting process. Lutein showed to be the major components of xanthophyll pigments brassica vegetables and ranged from 0.462μm·g^-1 in cabbage to 0.626μm·g^-1 in kohlrabi but not differed significantly which may refer to genetically controlled. However, lutein, antheraxanthin and zeaxanthin content were increased significantly by the application of chicken manure regardless ofbrassica vegetable type. Violaxanthin was only detected in pak choi and not affected by fertilizer source. It can be concluding from the increasing contents of total xanthophylls pigments that may increase photosynthetic efficiency through non-photochemical quenching process.展开更多
Most research on micronutrients in maize has focused on maize grown as a monocrop. The aim of this study was to determine the effects of intercropping on the concentrations of micronutrients in maize grain and their a...Most research on micronutrients in maize has focused on maize grown as a monocrop. The aim of this study was to determine the effects of intercropping on the concentrations of micronutrients in maize grain and their acquisition via the shoot. We conducted field experiments to investigate the effects of intercropping with turnip (Brassica campestris L.), faba bean (Vicia faba L.), chickpea (Cicer arietinum L.), and soybean (Glycine max L.) on the iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) concentrations in the grain and their acquisition via the above-ground shoots of maize (Zea mays L.). Compared with monocropped maize grain, the grain of maize intercropped with legumes showed lower concentrations of Fe, Mn, Cu, and Zn and lower values of their corresponding harvest indexes. The micronutrient concentrations and harvest indexes in grain of maize intercropped with turnip were the same as those in monocropped maize grain. Intercropping stimulated the above-ground maize shoot acquisition of Fe, Mn, Cu and Zn, when averaged over different phosphorus (P) application rates. To our knowledge, this is the first report on the effects of intercropping on micronutrient concentrations in maize grain and on micronutrients acquisition via maize shoots (straw+grain). The maize grain Fe and Cu concentrations, but not Mn and Zn concentrations, were negatively correlated with maize grain yields. The concentrations of Fe, Mn, Cu, and Zn in maize grain were positively correlated with their corresponding harvest indexes. The decreased Fe, Mn, Cu, and Zn concentrations in grain of maize intercropped with legumes were attributed to reduced translocation of Fe, Mn, Cu, and Zn from vegetative tissues to grains. This may also be related to the delayed senescence of maize plants intercropped with legumes. We conclude that turnip/maize intercropping is beneficial to obtain high maize grain yield without decreased concentrations of Fe, Mn, Cu, and Zn in the grain. Further research is required to clarify the mechanisms underlying the changes in micronutrient concentrations in grain of intercropped maize.展开更多
文摘Effect of fertilizer source （mineral fertilizer or organic manure） on photosynthetic pigments leaves content of four brassica vegetables （Pak choi, Kohlrabi, Cauliflower and Cabbage） was tested. Among treatments, cauliflower fertilized with chicken manure had the highest content of chlorophyll a and b （10.08 and 9.37 μm·g^-1）, while, pak choi had the lowest values （2.00 and 2.44 μm·g^-1） in non-fertilized plants. These differences in chlorophyll a and b content may have a great impact on photosynthetic rate and activity. Total carotenoids and total xanthophylls （lutein, zeaxanthin, antheraxanthin and violaxanthin） were the highest in cauliflower while the lowest was in pakchoi, β-carotene, on the other hand, was the highest percentage of total carotenoids （65.7%） in pak choi while Kohlrabi had the lowest percent （57.4%）. This high percentage offl-carotene of total carotenoids may compensate for lower content of chlorophylls and assist for efficient light harvesting process. Lutein showed to be the major components of xanthophyll pigments brassica vegetables and ranged from 0.462μm·g^-1 in cabbage to 0.626μm·g^-1 in kohlrabi but not differed significantly which may refer to genetically controlled. However, lutein, antheraxanthin and zeaxanthin content were increased significantly by the application of chicken manure regardless ofbrassica vegetable type. Violaxanthin was only detected in pak choi and not affected by fertilizer source. It can be concluding from the increasing contents of total xanthophylls pigments that may increase photosynthetic efficiency through non-photochemical quenching process.
基金supported by the National Natural Science Foundation of China (30890133)the National Basic Research Program of China (2011CB100405)China Agricultural University Specialized Research Fund to Support Ph.D. Candidates Innovative and Independent Scientific Subject(KYCX2010075)
文摘Most research on micronutrients in maize has focused on maize grown as a monocrop. The aim of this study was to determine the effects of intercropping on the concentrations of micronutrients in maize grain and their acquisition via the shoot. We conducted field experiments to investigate the effects of intercropping with turnip (Brassica campestris L.), faba bean (Vicia faba L.), chickpea (Cicer arietinum L.), and soybean (Glycine max L.) on the iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) concentrations in the grain and their acquisition via the above-ground shoots of maize (Zea mays L.). Compared with monocropped maize grain, the grain of maize intercropped with legumes showed lower concentrations of Fe, Mn, Cu, and Zn and lower values of their corresponding harvest indexes. The micronutrient concentrations and harvest indexes in grain of maize intercropped with turnip were the same as those in monocropped maize grain. Intercropping stimulated the above-ground maize shoot acquisition of Fe, Mn, Cu and Zn, when averaged over different phosphorus (P) application rates. To our knowledge, this is the first report on the effects of intercropping on micronutrient concentrations in maize grain and on micronutrients acquisition via maize shoots (straw+grain). The maize grain Fe and Cu concentrations, but not Mn and Zn concentrations, were negatively correlated with maize grain yields. The concentrations of Fe, Mn, Cu, and Zn in maize grain were positively correlated with their corresponding harvest indexes. The decreased Fe, Mn, Cu, and Zn concentrations in grain of maize intercropped with legumes were attributed to reduced translocation of Fe, Mn, Cu, and Zn from vegetative tissues to grains. This may also be related to the delayed senescence of maize plants intercropped with legumes. We conclude that turnip/maize intercropping is beneficial to obtain high maize grain yield without decreased concentrations of Fe, Mn, Cu, and Zn in the grain. Further research is required to clarify the mechanisms underlying the changes in micronutrient concentrations in grain of intercropped maize.
