Napier grass （Pennisetum purpureum Schumach）, a C4 tropical plant, has high dry matter productivity and sustainability without the need for renovating every year due to good overwintering ability and the absence of ...Napier grass （Pennisetum purpureum Schumach）, a C4 tropical plant, has high dry matter productivity and sustainability without the need for renovating every year due to good overwintering ability and the absence of serious pathogens or insects injury. This grass is suitable for multipurpose use, providing forage, bioethanol feedstock and phytoremediation of cadmium （Cd） contaminated soil in Kyushu, Japan. When two cultivars of Napier grass （Wruk wona, WK and Merkeron, ME） were grown in Cd-contaminated soils, dry matter yield and the concentration and uptake of herbage Cd were higher in WK than in ME, and soil Cd concentration was reduced by 14% in a single season of cultivation. A dwarf variety of late-heading type （DL）, Napier grass had superior sustainability for more than 5 years in Miyazaki, Japan, and has gradually increased in cultivation areas for both cut-and-carry and grazing herbage production in cooperation with regional communities. Through the extension in several Kyushu areas, DL Napier grass required temperatures above -6.2 ~C for sustainability in winter, based on its threshold response to the lethal minimum temperature. DL Napier grass pasture can be utilized by grazing beef cattle even in early spring with temperate Italian ryegrass inter-sown into its inter-row spaces. Organic digested animal manure or sun-dried leguminous leaves as green manure can replace chemical fertilizers to reduce energy consumption and allow comparable productivity.展开更多
A study was conducted in the forest area of Chittagong （South） Forest Division, Chittagong, Bangladesh for developing al- lometric models to estimate biomass organic carbon stock in the forest vegetation. Allometric...A study was conducted in the forest area of Chittagong （South） Forest Division, Chittagong, Bangladesh for developing al- lometric models to estimate biomass organic carbon stock in the forest vegetation. Allometric models were tested separately for trees （divided into two DBH classes）, shrubs, herbs and grasses. Model using basal area alone was found to be the best predictor of biomass organic carbon stock in trees because of high coefficient of determination （r^2 is 0.73697 and 0.87703 for 〉 5 cm to ≤ 15 cm and 〉 15 cm DBH （diameter at breast height） rang, respectively） and significance of regression （P is 0.000 for each DBH range） coefficients for both DBH range. The other models using height alone; DBH alone; height and DBH together; height, DBH and wood density; with liner and logarithmic relations produced relatively poor coefficient of determination. The allometric models for dominant 20 tree species were also developed separately and equation using basal area produced higher value of determination of coefficient. Allometric model using total biomass alone for shrubs, herbs and grasses produced higher value of determination of coefficient and significance of regression coefficient （r^2 is 0.87948 and 0.87325 for shrubs, herbs and grasses, respectively and P is 0.000 for each）. The estimation of biomass organic carbon is a complicated and time consuming research. The allometric models developed in the present study can be utilized for future estimation of organic carbon stock in forest vegetation in Bangladesh as well as other tropical countries of the world.展开更多
Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen...Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.展开更多
Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilizati...Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilization treatments and their combination to increase forage yield and quality grown under sandy soil conditions. The experiment included the combination of five mixing ratios (Egyptian clover alone, ryegrass alone, 75% Egyptian clover: 25% ryegrass, 50% Egyptian clover: 50% ryegrass and 25% Egyptian clover: 75% ryegrass) and eight fertilizer sources, which include control, organic fertilization, bio fertilization, chemical fertilizer, organic + bio fertilizer, organic + chemical fertilizer, bio + chemical fertilizer and combination of organic and chemical and bio fertilizers. The obtained results indicate the superiority of 75% E. clover: 25% ryegrass mixture fertilizedby Bio + O + N in fresh and dry forage production. On the other hand, it reported the lowest dry weight of weeds g/m2. Chemical analysis of forage plants showed that the mixture of ?75% E. clover: 25% ryegrass surpassed that of other treatments yield for crude protein, ether extract and ash. The results also revealed that the highest record of DCP, crude fiber and TDNY was obtained by forage mixture of 75% E. clover: 25% ryegrass fertilized with Bio + O + N. Such higher yield of these characters hassecured a balanced ratio which is really needed for ruminants ration.展开更多
文摘Napier grass （Pennisetum purpureum Schumach）, a C4 tropical plant, has high dry matter productivity and sustainability without the need for renovating every year due to good overwintering ability and the absence of serious pathogens or insects injury. This grass is suitable for multipurpose use, providing forage, bioethanol feedstock and phytoremediation of cadmium （Cd） contaminated soil in Kyushu, Japan. When two cultivars of Napier grass （Wruk wona, WK and Merkeron, ME） were grown in Cd-contaminated soils, dry matter yield and the concentration and uptake of herbage Cd were higher in WK than in ME, and soil Cd concentration was reduced by 14% in a single season of cultivation. A dwarf variety of late-heading type （DL）, Napier grass had superior sustainability for more than 5 years in Miyazaki, Japan, and has gradually increased in cultivation areas for both cut-and-carry and grazing herbage production in cooperation with regional communities. Through the extension in several Kyushu areas, DL Napier grass required temperatures above -6.2 ~C for sustainability in winter, based on its threshold response to the lethal minimum temperature. DL Napier grass pasture can be utilized by grazing beef cattle even in early spring with temperate Italian ryegrass inter-sown into its inter-row spaces. Organic digested animal manure or sun-dried leguminous leaves as green manure can replace chemical fertilizers to reduce energy consumption and allow comparable productivity.
文摘A study was conducted in the forest area of Chittagong （South） Forest Division, Chittagong, Bangladesh for developing al- lometric models to estimate biomass organic carbon stock in the forest vegetation. Allometric models were tested separately for trees （divided into two DBH classes）, shrubs, herbs and grasses. Model using basal area alone was found to be the best predictor of biomass organic carbon stock in trees because of high coefficient of determination （r^2 is 0.73697 and 0.87703 for 〉 5 cm to ≤ 15 cm and 〉 15 cm DBH （diameter at breast height） rang, respectively） and significance of regression （P is 0.000 for each DBH range） coefficients for both DBH range. The other models using height alone; DBH alone; height and DBH together; height, DBH and wood density; with liner and logarithmic relations produced relatively poor coefficient of determination. The allometric models for dominant 20 tree species were also developed separately and equation using basal area produced higher value of determination of coefficient. Allometric model using total biomass alone for shrubs, herbs and grasses produced higher value of determination of coefficient and significance of regression coefficient （r^2 is 0.87948 and 0.87325 for shrubs, herbs and grasses, respectively and P is 0.000 for each）. The estimation of biomass organic carbon is a complicated and time consuming research. The allometric models developed in the present study can be utilized for future estimation of organic carbon stock in forest vegetation in Bangladesh as well as other tropical countries of the world.
基金financially supported by the National Key R&D Program of China(2019YFD0900200,2018YFD0900400)Supported by the earmarked fund for CARS(CARS-45)+2 种基金National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)the Young Top-Notch Talent Support ProgramSichuan Science and Technology Program(2019YFN0036)。
文摘Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.
文摘Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilization treatments and their combination to increase forage yield and quality grown under sandy soil conditions. The experiment included the combination of five mixing ratios (Egyptian clover alone, ryegrass alone, 75% Egyptian clover: 25% ryegrass, 50% Egyptian clover: 50% ryegrass and 25% Egyptian clover: 75% ryegrass) and eight fertilizer sources, which include control, organic fertilization, bio fertilization, chemical fertilizer, organic + bio fertilizer, organic + chemical fertilizer, bio + chemical fertilizer and combination of organic and chemical and bio fertilizers. The obtained results indicate the superiority of 75% E. clover: 25% ryegrass mixture fertilizedby Bio + O + N in fresh and dry forage production. On the other hand, it reported the lowest dry weight of weeds g/m2. Chemical analysis of forage plants showed that the mixture of ?75% E. clover: 25% ryegrass surpassed that of other treatments yield for crude protein, ether extract and ash. The results also revealed that the highest record of DCP, crude fiber and TDNY was obtained by forage mixture of 75% E. clover: 25% ryegrass fertilized with Bio + O + N. Such higher yield of these characters hassecured a balanced ratio which is really needed for ruminants ration.
