A greenhouse pot experiment was conducted to investigate the in?uence of soil moisture content on plant growth and the rhizosphere microbial community structure of four plant species (white clover, alfalfa, sudan gras...A greenhouse pot experiment was conducted to investigate the in?uence of soil moisture content on plant growth and the rhizosphere microbial community structure of four plant species (white clover, alfalfa, sudan grass, tall fescue), grown individually or in a mixture. The soil moisture content was adjusted to 55% or 80% water holding capacity (WHC). The results indicated that the total plant biomass of one pot was lower at 55% WHC. At a given soil moisture, the total plant biomass of white clover and tall ...展开更多
Through analyzing statistically metrological observation data from 1971 to 2010 and pasture data from 1983 to 2012 at 6 animal husbandry meteorological testing stations of Inner Mongolia grassland, the conclusions wer...Through analyzing statistically metrological observation data from 1971 to 2010 and pasture data from 1983 to 2012 at 6 animal husbandry meteorological testing stations of Inner Mongolia grassland, the conclusions were drawn. Those were that annual average temperature rose in a straight line in Inner Mongolia grassland, and the increase rates of annual average temperature in meadow steppe and typical steppe were 0.40 and 0.34 ℃/10 a respectively. Annual rainfall had 10-year cyclical characteristics, and precipitation in the 1990s was the most but reduced significantly after 2000. Climate experienced the cold wet -cold dry -warm wet -warm dry periods. Warm and dry climate made the average heights of pasture in meadow steppe and typical steppe of Inner Mongolia cut down 2.4 and 9.3 cm in nearly 12 years than that in the 1990s; the average coverage of herbage decreased by 11% and 13%; the average hay yields reduced by 1 019.8 and 671.4 kg/hm^2.展开更多
The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and t...The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and to evaluate the allelopathic effect of these metabolites on forage legumes for intercropping. Phytochemical prospecting analyses, 1H NMR and capillary electrophoresis were performed on extracts of U. humidicola. Allelopathic activity was evaluated in germination of Stylosanthes, Macrotyloma axillare and Lactuca sativa L. (standard) in the presence of crude extracts, isolated saponins, flavonoids and trans-cinnamic acid. The metabolite classes present in the extracts could be determined by the combined use of the tested analytical techniques, but their use alone was usually not sufficient to chemically characterize the species. Capillary electrophoresis was effective in detecting phenolic compounds. Macrotyloma axillare was tolerant to crude extracts of U. humidicola. Saponins and trans-cinnamic acid, but not the flavonoids, reduced germination of the target plants.展开更多
This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The ...This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The study was performed by using randomized block design(RBD)with eight treatments(S0:no introduction,S1:Cynodon dactilon,S2:Dicanthium aristatum,S3:C.plectotachyus,S4:Brachiaria decumbens,S5:Desmanthus virgatus,S6:Macroptilium atropurpureum,S7:Clitoria ternatea)with four replications.Procedures on this study include trial plots preparation,tillers preparation for each species,introduction of species in trial plots,maintenance and observation of the productivity.Variables observed were forage production(fresh and dry matter(DM)in ton/ha),nutrient content(%)and stock capacity(animal unit(AU)/ha).Data were analyzed for variance based on RBD and followed by Duncan’s test.Analysis of variance showed that introduction of species had a very significant effect(p<0.01)on all observed variables.The introduction of M.atropurpureum produced the highest fresh forage(2.1 t/ha)and DM production(0.69 t/ha).M.atropurpureum also had the highest DM content(43.61%),nitrogen free extract(52.52%)and stock capacity(1.06 AU/ha).The highest crude protein and crude fiber content were found in D.virgatus(4.31%and 36.62%).The highest extract ether was observed in D.aristatum(1.48%).No introduction had the lowest productivity,but demonstrated the highest ash content.The introduction of palatable species increased the productivity of native pasture in Timor and M.atropupureum was the best introduced species.展开更多
Alfalfa is a high quality forage that is not often utilized in the southeastern United States because of its perceived lack of adaptability to the area. However, the risk of growing alfalfa could be partially mitigate...Alfalfa is a high quality forage that is not often utilized in the southeastern United States because of its perceived lack of adaptability to the area. However, the risk of growing alfalfa could be partially mitigated by its inclusion into an existing bermudagrass system that makes up a large portion of pastures and hay fields in Mississippi. Alfalfa was planted into an existing bermudagrass hay field at a rate of 17, 22, 28 and 39 kg·ha-1 in no-till and minimum till sod preparation and analyzed for three growing seasons. Tillage did not affect any of the variables observed but seeding rate and time affected DM (dry matter) yield, forage nutritive value and plot composition. The increasing alfalfa seeding rate increased alfalfa yield in the plot but this was isolated to only the first year. Dry matter yields decreased over the three years due to the decrease in alfalfa composition, but throughout the growing season DM yields increased after the first year suggesting bermudagrass recolonization within the plot. Forage nutritive value was positively affected with as little as 20% of the plot composed of alfalfa suggesting that even thinning stands by the third year might offer economic advantages.展开更多
A field experiment was carried out at the CSIC Muñovela farm belonging to the Spanish National Research Council (CSIC) in order to evaluate the effect of sowing orchard grass (Dactylis glomerata var. Trerano) ...A field experiment was carried out at the CSIC Muñovela farm belonging to the Spanish National Research Council (CSIC) in order to evaluate the effect of sowing orchard grass (Dactylis glomerata var. Trerano) and lucerne (Medicago sativa var. Aragon) in monoculture and in combination. The experiment was based on a randomized block designed with a factorial arrangement (5 × 2). Experimental units were 40 plots distributed in four blocks. The phosphorus fertilization (P) factor included two types of conditions: basal fertilization without phosphorus (-P) and basal fertilization with phosphorus (+P), and the vegetation cover factor (T) included five conditions depending on the grass (G) and the legume (L). Above-ground biomass showed statistically significant differences among seasons and years (P Lolium perenne L. and Poa pratensis L. throughout the three years indicated that both species significantly increased their presence over time regardless of the treatments applied. The analysis performed for the other plant species (those other than grasses and legumes) allowed us to determine that the T1 and T5 treatments, which correspond to single species not treated with the application of phosphorus, influenced the presence of 70% of other species planted. Our specific aim was to explore how changing plant biotic diversity affects productivity under a given set of conditions. We manipulated plant species richness as an experimental factor to determine if productivity would be affected by changes in the ratios of plants sown.展开更多
The objective of this study was to evaluate alternative methods of grassland renewal (reseeding) with perennial ryegrass and quantify their effects on subsequent DM yield, tiller density and nitrate leaching. Two expe...The objective of this study was to evaluate alternative methods of grassland renewal (reseeding) with perennial ryegrass and quantify their effects on subsequent DM yield, tiller density and nitrate leaching. Two experiments were carried out;the first focused on quantifying the influence of Autumn reseeding (August cultivation), and the second, on Spring reseeding (May cultivation) on sward establishment and grass DM production. The study incorporated six treatments namely: direct drill (DD), disc plus power harrow (DPH), power harrow (PH), conventional-plough, till and sow (PLO), and the chemical application of diquat to suppress the existing sward followed by direct drilling (DIQ), represented a rejuvenation method as opposed to full renewal (Spring trial only). All treatments were compared against a control (old permanent pasture). Reseeded swards produced more seasonal (P < 0.05) and total (P < 0.01 Autumn only) DM yield than the control sward. All reseeding methods increased the perennial ryegrass tiller density of the sward compared to the old permanent pasture (P < 0.05 Autumn trial, P < 0.001 Spring trial). All sward renewal methods evaluated were equally as effective as the conventional method of grassland reseeding with the DIQ rejuvenation method intermediate as measured in terms of DM yield and PRG tiller density. The results of the study show no significant difference in the level of nitrate lost in leachate following reseeding regardless of method used or indeed any difference between reseeded swards and old permanent pasture.展开更多
Our objective was to evaluate the combining ability among cultivars of forage species, commonly sown in temperate regions of Argentina using a short rotation system. Three genetically diverse cultivars of prairie brom...Our objective was to evaluate the combining ability among cultivars of forage species, commonly sown in temperate regions of Argentina using a short rotation system. Three genetically diverse cultivars of prairie brome grass (Bromus catharticus, cv Copetona, cv ?andú and cv Tango), a white clover cultivar (Trifolium repens, cv Lucero) and a red clover cultivar (T. pratense, cv Tropero) were evaluated. A randomized complete block design experiment was established in 2005. The treatments included five monocultures and ten binary mixtures. The experiment was harvested 6 times over an 18-month period. Cumulative dry matter yield (kg?ha–1) was calculated as the sum of the six individual harvests. Diallel analysis provided estimates of the general combining ability (GCA) and specific combining ability (SCA). Red clover in monoculture and mixtures produced the highest yields, with significant positive GCA effects (P P P P < 0.01). Given the short-term nature of this study, we must limit our inference to short-term pastures (<2 years). Under these conditions, red clover had the best combination with prairie brome grass.展开更多
基金the National Natural Science Foundation of China (No. 40621061)the National Basic Research Program (973) of China(No. 2005CB121105)
文摘A greenhouse pot experiment was conducted to investigate the in?uence of soil moisture content on plant growth and the rhizosphere microbial community structure of four plant species (white clover, alfalfa, sudan grass, tall fescue), grown individually or in a mixture. The soil moisture content was adjusted to 55% or 80% water holding capacity (WHC). The results indicated that the total plant biomass of one pot was lower at 55% WHC. At a given soil moisture, the total plant biomass of white clover and tall ...
基金Supported by Science Technology Innovation Item of Inner Mongolia Meteorological Bureau,China(nmgqxkjcx201115)
文摘Through analyzing statistically metrological observation data from 1971 to 2010 and pasture data from 1983 to 2012 at 6 animal husbandry meteorological testing stations of Inner Mongolia grassland, the conclusions were drawn. Those were that annual average temperature rose in a straight line in Inner Mongolia grassland, and the increase rates of annual average temperature in meadow steppe and typical steppe were 0.40 and 0.34 ℃/10 a respectively. Annual rainfall had 10-year cyclical characteristics, and precipitation in the 1990s was the most but reduced significantly after 2000. Climate experienced the cold wet -cold dry -warm wet -warm dry periods. Warm and dry climate made the average heights of pasture in meadow steppe and typical steppe of Inner Mongolia cut down 2.4 and 9.3 cm in nearly 12 years than that in the 1990s; the average coverage of herbage decreased by 11% and 13%; the average hay yields reduced by 1 019.8 and 671.4 kg/hm^2.
文摘The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and to evaluate the allelopathic effect of these metabolites on forage legumes for intercropping. Phytochemical prospecting analyses, 1H NMR and capillary electrophoresis were performed on extracts of U. humidicola. Allelopathic activity was evaluated in germination of Stylosanthes, Macrotyloma axillare and Lactuca sativa L. (standard) in the presence of crude extracts, isolated saponins, flavonoids and trans-cinnamic acid. The metabolite classes present in the extracts could be determined by the combined use of the tested analytical techniques, but their use alone was usually not sufficient to chemically characterize the species. Capillary electrophoresis was effective in detecting phenolic compounds. Macrotyloma axillare was tolerant to crude extracts of U. humidicola. Saponins and trans-cinnamic acid, but not the flavonoids, reduced germination of the target plants.
文摘This research was aimed to evaluate the productivity of native pasture in Timor Island by introducing various palatable species.The study was carried out on native pasture in Tuatuka,Timor Island for seven months.The study was performed by using randomized block design(RBD)with eight treatments(S0:no introduction,S1:Cynodon dactilon,S2:Dicanthium aristatum,S3:C.plectotachyus,S4:Brachiaria decumbens,S5:Desmanthus virgatus,S6:Macroptilium atropurpureum,S7:Clitoria ternatea)with four replications.Procedures on this study include trial plots preparation,tillers preparation for each species,introduction of species in trial plots,maintenance and observation of the productivity.Variables observed were forage production(fresh and dry matter(DM)in ton/ha),nutrient content(%)and stock capacity(animal unit(AU)/ha).Data were analyzed for variance based on RBD and followed by Duncan’s test.Analysis of variance showed that introduction of species had a very significant effect(p<0.01)on all observed variables.The introduction of M.atropurpureum produced the highest fresh forage(2.1 t/ha)and DM production(0.69 t/ha).M.atropurpureum also had the highest DM content(43.61%),nitrogen free extract(52.52%)and stock capacity(1.06 AU/ha).The highest crude protein and crude fiber content were found in D.virgatus(4.31%and 36.62%).The highest extract ether was observed in D.aristatum(1.48%).No introduction had the lowest productivity,but demonstrated the highest ash content.The introduction of palatable species increased the productivity of native pasture in Timor and M.atropupureum was the best introduced species.
文摘Alfalfa is a high quality forage that is not often utilized in the southeastern United States because of its perceived lack of adaptability to the area. However, the risk of growing alfalfa could be partially mitigated by its inclusion into an existing bermudagrass system that makes up a large portion of pastures and hay fields in Mississippi. Alfalfa was planted into an existing bermudagrass hay field at a rate of 17, 22, 28 and 39 kg·ha-1 in no-till and minimum till sod preparation and analyzed for three growing seasons. Tillage did not affect any of the variables observed but seeding rate and time affected DM (dry matter) yield, forage nutritive value and plot composition. The increasing alfalfa seeding rate increased alfalfa yield in the plot but this was isolated to only the first year. Dry matter yields decreased over the three years due to the decrease in alfalfa composition, but throughout the growing season DM yields increased after the first year suggesting bermudagrass recolonization within the plot. Forage nutritive value was positively affected with as little as 20% of the plot composed of alfalfa suggesting that even thinning stands by the third year might offer economic advantages.
文摘A field experiment was carried out at the CSIC Muñovela farm belonging to the Spanish National Research Council (CSIC) in order to evaluate the effect of sowing orchard grass (Dactylis glomerata var. Trerano) and lucerne (Medicago sativa var. Aragon) in monoculture and in combination. The experiment was based on a randomized block designed with a factorial arrangement (5 × 2). Experimental units were 40 plots distributed in four blocks. The phosphorus fertilization (P) factor included two types of conditions: basal fertilization without phosphorus (-P) and basal fertilization with phosphorus (+P), and the vegetation cover factor (T) included five conditions depending on the grass (G) and the legume (L). Above-ground biomass showed statistically significant differences among seasons and years (P Lolium perenne L. and Poa pratensis L. throughout the three years indicated that both species significantly increased their presence over time regardless of the treatments applied. The analysis performed for the other plant species (those other than grasses and legumes) allowed us to determine that the T1 and T5 treatments, which correspond to single species not treated with the application of phosphorus, influenced the presence of 70% of other species planted. Our specific aim was to explore how changing plant biotic diversity affects productivity under a given set of conditions. We manipulated plant species richness as an experimental factor to determine if productivity would be affected by changes in the ratios of plants sown.
文摘The objective of this study was to evaluate alternative methods of grassland renewal (reseeding) with perennial ryegrass and quantify their effects on subsequent DM yield, tiller density and nitrate leaching. Two experiments were carried out;the first focused on quantifying the influence of Autumn reseeding (August cultivation), and the second, on Spring reseeding (May cultivation) on sward establishment and grass DM production. The study incorporated six treatments namely: direct drill (DD), disc plus power harrow (DPH), power harrow (PH), conventional-plough, till and sow (PLO), and the chemical application of diquat to suppress the existing sward followed by direct drilling (DIQ), represented a rejuvenation method as opposed to full renewal (Spring trial only). All treatments were compared against a control (old permanent pasture). Reseeded swards produced more seasonal (P < 0.05) and total (P < 0.01 Autumn only) DM yield than the control sward. All reseeding methods increased the perennial ryegrass tiller density of the sward compared to the old permanent pasture (P < 0.05 Autumn trial, P < 0.001 Spring trial). All sward renewal methods evaluated were equally as effective as the conventional method of grassland reseeding with the DIQ rejuvenation method intermediate as measured in terms of DM yield and PRG tiller density. The results of the study show no significant difference in the level of nitrate lost in leachate following reseeding regardless of method used or indeed any difference between reseeded swards and old permanent pasture.
基金Commercial cultivars seed used in this research were kindly provided by GAPP semillas S.A.and Gentos S.A,Argentina.Anonymous suggestions are acknowledged.
文摘Our objective was to evaluate the combining ability among cultivars of forage species, commonly sown in temperate regions of Argentina using a short rotation system. Three genetically diverse cultivars of prairie brome grass (Bromus catharticus, cv Copetona, cv ?andú and cv Tango), a white clover cultivar (Trifolium repens, cv Lucero) and a red clover cultivar (T. pratense, cv Tropero) were evaluated. A randomized complete block design experiment was established in 2005. The treatments included five monocultures and ten binary mixtures. The experiment was harvested 6 times over an 18-month period. Cumulative dry matter yield (kg?ha–1) was calculated as the sum of the six individual harvests. Diallel analysis provided estimates of the general combining ability (GCA) and specific combining ability (SCA). Red clover in monoculture and mixtures produced the highest yields, with significant positive GCA effects (P P P P < 0.01). Given the short-term nature of this study, we must limit our inference to short-term pastures (<2 years). Under these conditions, red clover had the best combination with prairie brome grass.