[Objectives]The paper was to systematically study the technology of weed control in alfalfa field.[Methods]Reviving alfalfa field and newly sown alfalfa field after emergence were selected,and the effects of different...[Objectives]The paper was to systematically study the technology of weed control in alfalfa field.[Methods]Reviving alfalfa field and newly sown alfalfa field after emergence were selected,and the effects of different herbicides on weed control and alfalfa yield were discussed.[Results]The optimal herbicides after alfalfa reviving were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 1.05 L/hm 2,respectively.The optimal herbicides after emergence of newly born alfalfa were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 0.75 L/hm 2,respectively.[Conclusions]This study will provide a technical support for high quality production of alfalfa.展开更多
The experiment aimed to investigate foliar fertilizer application effects on amino acid content of Indigofera leaves. lndigofera arrecta was planted in plots during both rainy and dry seasons. Foliar fertilizer concen...The experiment aimed to investigate foliar fertilizer application effects on amino acid content of Indigofera leaves. lndigofera arrecta was planted in plots during both rainy and dry seasons. Foliar fertilizer concentrations consisted of 10 g, 20 g, 30 g, 40 g and 50 g, which solved in 10 L solvent were appIied on sixteen individual plants per plot, The fertilizer was applied 4 times during vegetative growing period. Block randomized design with 3 replications was used in this experiment. The foliar fertilizer containing 20%-22% N （N total）, 15%-16% P （P205）, 15%-16% K, 1.5% Mg, 1% Ca, 1% Fe, 1.42% Zn, 0.53% Cu, 0.88% Mo, 0.53% B and growth hormone 0.025% indole acetic acid （1AA） and giberelic acid （GA） was applied. Samples of each plot were composited leaves from 3 harvest times. The result showed that the foliar fertilizer did not affect aspartic acid, seriue, histidine, threonine, tyrosine, valine, methionine, iso-leusine and leusine content oflndigofera leave. Foliar fertilizer application up to 50 g/10 L resulted in higher （P 〈 0.05） glutamate acid, glysine, arginine, alanine, proline and lysine than those of other fertilizer levels.展开更多
Aims Grasslands are widely used for production of livestock,which depend on the nutritive value of herbage species.However,there are still large uncertainties as to how grazing,precipitation and growing season interac...Aims Grasslands are widely used for production of livestock,which depend on the nutritive value of herbage species.However,there are still large uncertainties as to how grazing,precipitation and growing season interactively affect herbage nutritive value.Methods Here,based on a grazing experiment with seven grazing intensities in an Inner Mongolian grassland since the year 2005,we analysed nutritive value of four dominant grass species from June to September in both a relatively wetter year(2008)and a drier year(2010).Herbage with high nutritive value is characterized by high concentration of crude protein,high concentration of cellulase digestible organic matter and low concentration of neutral detergent fibre.Important Findings We found that(i)grazing significantly increased the nutritive value of Leymus chinensis,Agropyron michnoi and Cleistogenes squarrosa but had minor effects on the nutritive value of Stipa grandis.(ii)For all species,nutritive values were greater in the wetter year than in the drier year and were greatest in the early growing season(June)and lowest at the end of the growing season(September).Inter-annual and inter-seasonal variations in nutritive value were much greater for L.chinensis and A.michnoi than for C.squarrosa and S.grandis,suggesting higher water use efficiency for the latter two species.(iii)Grazing significantly decreased the drought resistance of three species,but not of S.grandis.(iv)Grazing significantly increased inter-month variation in nutritive value for L.chinensis and A.michnoi but had relatively minor or no effects on that of C.squarrosa and S.grandis.Therefore,grazing effects on species nutritive values showed strong inter-annual and seasonal patterns,and species-specific responses might be related to species traits(i.e.water use efficiency,digestibility).Our results have important implications for ecosystem management of arid and semiarid grasslands under intense grazing and global climatic change.展开更多
Over the past 70 years,the world has witnessed extraordinary growth in crop productivity,enabled by a suite of technological advances,including higher yielding crop varieties,improved farm management,synthetic agroche...Over the past 70 years,the world has witnessed extraordinary growth in crop productivity,enabled by a suite of technological advances,including higher yielding crop varieties,improved farm management,synthetic agrochemicals,and agricultural mechanization.While this"Green Revolution"intensified crop production,and is credited with reducing famine and malnutrition,its benefits were accompanied by several undesirable collateral effects(Pingali,2012).These include a narrowing of agricultural biodiversity,stemming from increased monoculture and greater reliance on a smaller number of crops and crop varieties for the majority of our calories.This reduction in diversity has created vulnerabilities to pest and disease epidemics,climate variation,and ultimately to human health(Harlan,1972).展开更多
文摘[Objectives]The paper was to systematically study the technology of weed control in alfalfa field.[Methods]Reviving alfalfa field and newly sown alfalfa field after emergence were selected,and the effects of different herbicides on weed control and alfalfa yield were discussed.[Results]The optimal herbicides after alfalfa reviving were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 1.05 L/hm 2,respectively.The optimal herbicides after emergence of newly born alfalfa were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 0.75 L/hm 2,respectively.[Conclusions]This study will provide a technical support for high quality production of alfalfa.
文摘The experiment aimed to investigate foliar fertilizer application effects on amino acid content of Indigofera leaves. lndigofera arrecta was planted in plots during both rainy and dry seasons. Foliar fertilizer concentrations consisted of 10 g, 20 g, 30 g, 40 g and 50 g, which solved in 10 L solvent were appIied on sixteen individual plants per plot, The fertilizer was applied 4 times during vegetative growing period. Block randomized design with 3 replications was used in this experiment. The foliar fertilizer containing 20%-22% N （N total）, 15%-16% P （P205）, 15%-16% K, 1.5% Mg, 1% Ca, 1% Fe, 1.42% Zn, 0.53% Cu, 0.88% Mo, 0.53% B and growth hormone 0.025% indole acetic acid （1AA） and giberelic acid （GA） was applied. Samples of each plot were composited leaves from 3 harvest times. The result showed that the foliar fertilizer did not affect aspartic acid, seriue, histidine, threonine, tyrosine, valine, methionine, iso-leusine and leusine content oflndigofera leave. Foliar fertilizer application up to 50 g/10 L resulted in higher （P 〈 0.05） glutamate acid, glysine, arginine, alanine, proline and lysine than those of other fertilizer levels.
基金Deutsche Forschungsgemeinschaft(DFG)for funding the research group 536 MAGIM(Matter fluxes of grasslands in Inner Mongolia as influenced by stocking rate)and the subsequent Lot-Grass projectthe Ministry of Education of China(IRT1259).
文摘Aims Grasslands are widely used for production of livestock,which depend on the nutritive value of herbage species.However,there are still large uncertainties as to how grazing,precipitation and growing season interactively affect herbage nutritive value.Methods Here,based on a grazing experiment with seven grazing intensities in an Inner Mongolian grassland since the year 2005,we analysed nutritive value of four dominant grass species from June to September in both a relatively wetter year(2008)and a drier year(2010).Herbage with high nutritive value is characterized by high concentration of crude protein,high concentration of cellulase digestible organic matter and low concentration of neutral detergent fibre.Important Findings We found that(i)grazing significantly increased the nutritive value of Leymus chinensis,Agropyron michnoi and Cleistogenes squarrosa but had minor effects on the nutritive value of Stipa grandis.(ii)For all species,nutritive values were greater in the wetter year than in the drier year and were greatest in the early growing season(June)and lowest at the end of the growing season(September).Inter-annual and inter-seasonal variations in nutritive value were much greater for L.chinensis and A.michnoi than for C.squarrosa and S.grandis,suggesting higher water use efficiency for the latter two species.(iii)Grazing significantly decreased the drought resistance of three species,but not of S.grandis.(iv)Grazing significantly increased inter-month variation in nutritive value for L.chinensis and A.michnoi but had relatively minor or no effects on that of C.squarrosa and S.grandis.Therefore,grazing effects on species nutritive values showed strong inter-annual and seasonal patterns,and species-specific responses might be related to species traits(i.e.water use efficiency,digestibility).Our results have important implications for ecosystem management of arid and semiarid grasslands under intense grazing and global climatic change.
文摘Over the past 70 years,the world has witnessed extraordinary growth in crop productivity,enabled by a suite of technological advances,including higher yielding crop varieties,improved farm management,synthetic agrochemicals,and agricultural mechanization.While this"Green Revolution"intensified crop production,and is credited with reducing famine and malnutrition,its benefits were accompanied by several undesirable collateral effects(Pingali,2012).These include a narrowing of agricultural biodiversity,stemming from increased monoculture and greater reliance on a smaller number of crops and crop varieties for the majority of our calories.This reduction in diversity has created vulnerabilities to pest and disease epidemics,climate variation,and ultimately to human health(Harlan,1972).
