Alfalfa (Medicago sativa L.) is the most widely cultivated perennial leguminous forage crop woldwide.Micro RNA156 (miR156) precursor genes from dicotyledonous species are reportedly useful for improving alfalfa plant ...Alfalfa (Medicago sativa L.) is the most widely cultivated perennial leguminous forage crop woldwide.Micro RNA156 (miR156) precursor genes from dicotyledonous species are reportedly useful for improving alfalfa plant architecture and abiotic stress resistance.However,there has been no report on whether a miR156 precursor gene from a monocotyledonous species functions in alfalfa.We introduced two tandem precursor genes of miR156,rice Osa-MIR156b and Osa-MIR156c (Osa-MIR156bc),into alfalfa.The expression of miR156 in the transgenic (TG) alfalfa was significantly elevated.Compared to wild-type plants,the TG plants overexpressing miR156 had more branches and leaves and showed improved salt and drought tolerance.Overexpression of miR156 slightly reduced plant height,but the biomass yield of TG plants grown in flowerpots was still increased.Forage quality of TG plants was markedly improved by reduction of acid detergent lignin (ADL) content and increase in crude protein content.The expression of the putative miR156 target genes Ms SPL6,Ms SPL12,and Ms SPL13 in TG plants was repressed by miR156overexpression,and that of all tested Ms SPLs would be sharply increased under drought or salt stress.RNA sequencing revealed that overexpression of miR156 affected the expression of genes associated with abiotic stress resistance and plant development in multiple pathways.This first report of overexpression of monocot miR156 precursors in alfalfa sheds light on the function of mi RNA156 precursors from the monocot species rice that could be used for genetic improvement of the dicot forage crop alfalfa.展开更多
The nutritional value of kudzu (Pueraria lobata) was evaluated as a potential animal feed. Randomly selected samples from natural habitats with Jacksonville area (Alabama, USA) were utilized in the study. Kudzu leaves...The nutritional value of kudzu (Pueraria lobata) was evaluated as a potential animal feed. Randomly selected samples from natural habitats with Jacksonville area (Alabama, USA) were utilized in the study. Kudzu leaves showed significantly higher dry matter and crude protein content than the stems;whereas, ADF fiber was significantly lower in the leaves. However, NDF and total digestible nutrients (TDN) were similar in the leaves and the stems. The leaf part of kudzu was especially rich in CP (24.46%) and met the requirements and recommendations for most ruminants. The TDN value for kudzu stem is 55.99%, which falls below but within the recommended range. Macronutrients concentration between the stem and leaf of kudzu, nitrogen, calcium, and magnesium showed a significantly higher in the leaf than the stem. However, phosphorous was similar in concentration in the stem and the leaf, and potassium was higher in the stem. In regard to the micronutrients, the only significant difference between the leaf and the stem was iron. However, iron, manganese, zinc, and copper were all above the recommended concentrations by the National Research Council. In general, kudzu can be considered a good source for animal feed, especially the leaf, which shows a higher value in most of the determined criteria in comparison to what was recommended by the National Research Council. This should provide a new outlook to kudzu, which has been considered a noxious weed and help in the utilization of kudzu in a positive way in the southern region of the US.展开更多
Thirty lactating Holstein cows were used to investigate the effects of different forages quality on milk fatty acids(FA) profiles and production. The cows were assigned to 3 dietary treatments(n = 10 per treatment) in...Thirty lactating Holstein cows were used to investigate the effects of different forages quality on milk fatty acids(FA) profiles and production. The cows were assigned to 3 dietary treatments(n = 10 per treatment) in a randomized block design with 3 repeated measures. They were fed the experimental diets for 90 d with 3 days of collection of samples for analysis at about 27 d intervals(samples were collected on days 28,29,30, 58, 59, 60.88, 89 and 90). The treatments were(DM basis): 1) mixed forages diet(MF) consisting of 3.7% Chinese wild rye, 26.7% corn silage and 23.4% alfalfa hay; 2) corn stalk diet 1(CS1) where corn stalk was used to formulate a similar chemical nutrient level to MF; 3) corn stalk diet 2(CS2) which used corn stalk to formulate a similar forage level to MF for the diet. Dry matter intake and BW were similar between treatments, but daily milk yield, milk fat and protein yield decreased(P < 0.05)in CS1 and CS2 compared with MF, with CS2 being the lowest(P < 0.05). In total FA of milk, the compositions of C18:1 c9, C18:3 and unsaturated FA increased(P < 0.05) in CS1 and CS2 compared with MF,and C18:0 and trans-C18:1 were trended to increase(P < 0.10), but C4:0-C16:0 were decreased(P < 0.05).Compared with cows fed CS2, cows receiving CS1 increased the compositions of C4:0 to C12:0 and C18:2(P < 0.05). The results suggests feeding corn stalk could produce a greater proportion of unsaturated fatty acid(UFA) in milk fat without resulting in milk fat depression(MFD) in mid lactation cows, but simply increasing the ratio of concentrate in low forages diets is not an effective way to increase milk fat synthesis and milk production.展开更多
Among the crop production factors,preceding crop and tillage management affect the sustainable use of soil resources and ultimately crop growth and productivity.This study aimed at investigating the impact of precedin...Among the crop production factors,preceding crop and tillage management affect the sustainable use of soil resources and ultimately crop growth and productivity.This study aimed at investigating the impact of preceding winter crops(grass or legume)and different tillage systems on forage yield,quality and nutritive values of three summer grass(Sudan grass,pearl millet and teosinte)and two legume forage crops(cowpea and guar)under arid conditions.The results exhibited that growing forage crops after legumes(as berseem clover)produced the highest fresh and dry forage yields and quality attributes compared with grasses(as wheat)with the exception of crude fiber content,which was decreased.Moreover,tillage practices showed positive impact on forage yields and quality attributes.The maximum forage yields and quality parameters were recorded under conventional tillage(CT)practice compared with reduced tillage(RT)and no-tillage(NT)systems.Among the evaluated crops,the highest yields of fresh forage,dry forage,crude fiber,crude protein and total digestible nutrient were exhibited by grass forage crops(Sudan grass,pearl millet and teosinte),whereas the highest crude protein content and the digestible energy values were produced by legume forage crops(cowpea and guar).The maximum fresh forage,dry forage,crude fiber,crude protein,total digestible nutrient and digestible crude protein yields were produced by pearl millet followed by Sudan grass under CT and RT after berseem clover.The highest net return was recorded by sowing pearl millet after berseem clover and applying CT followed by RT practices,which could be recommended for the commercial production.Moreover,it could be assumed that the combination of growing grass forage crops after legume crops under CT or RT systems could enhance forage crop yield and quality with an improvement in soil properties for sustainable agriculture with low cost and the highest net income.展开更多
In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.T...In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.The results showed that compared with the B.napus L.varieties,the growth period of B.campestris L.was shortened by 10-15 d,the overwintering rate(WR)increased by 50.6%,and the density after winter(PD)increased by 41.5%.The fresh forage yield(FFY)and dry forage yield(DFY)of the B.campestris L.type significantly increased by 40.9%and 38.1%compared with the B.napus L.type.,respectively,while the forage quality of the B.napus L.type rape was significantly better than that of the B.campestris L.type.Compared with the B.campestris L.type,the crude protein(CP),fat,ash and total fatty acid(TFA)contents of the B.napus L.type of rape increased by 27.6%,42.9%,23.9%and 52.3%,respectively,and the milk productivity(HM),relative forage value(RFV)and relative forage quality(RFQ)increased by 14.0%,16.2%and 42.1%,respectively.The light and heat resources before wintering increased the WR and PD(P<0.05),and were positively correlated with FFY and DFY(P>0.05),and lower temperature during the wintering period led to lower WR(P<0.01).The light and heat resources during the overwintering period and after regreening were negatively correlated with FFY and DFY(P>0.05).The contents of CP,fat and TFA of rape had an extremely significant negative correlation with the temperature and sunshine hours before wintering,but an extremely significant positive correlation with the temperature during the wintering period and after regreening,as well as the sunshine hours and rainfall during the wintering period;and HM had an extremely significant positive correlation with the temperature,sunshine hours and rainfall during the wintering period,while RFV and RFQ were only extremely significantly positively correlated with the maximum temperature and rainfall.In summary,in the North China Plain,for autumn sowing rape,the B.campestris L.type can be selected to improve the wintering rate,and the B.napus L.type should be the main choice to improve the forage quality of rape.Therefore,the B.napus L.variety HYZ62 can be selected for autumn sowing in the North China Plain.展开更多
A pool experiment was carried out to study the effects of different nitrogen applicationstrategies (rates and stages of nitrogen application) on yield and forage nutritivequality of Zea mexicana cultivated in summer, ...A pool experiment was carried out to study the effects of different nitrogen applicationstrategies (rates and stages of nitrogen application) on yield and forage nutritivequality of Zea mexicana cultivated in summer, 2002. In the whole growing stage, its stemwas clipped three times at the height of 25cm when it was 110cm high (H1, H2 and H3 standfor the first, second and third harvest stage, respectively). Six indexes includingcrude protein (CP), ether extract (EE), nitrogen free extract (NFE), acid detergentfiber (ADF), crude ash (CA), and general energy (GE) were employed to evaluate the foragenutritive value. The results showed that the content of CP and EE increased but thecontent of CA and ADF decreased under the two nitrogen rates (High-rate N, 600kgha-1;Mid-rate N, 300kgha-1). The fresh and dry harvest biomass of the whole plants on H1 andthose of the leaves on H2 were also improved. But the stalks on H2 and the whole plantson H3 were affected mainly by dressing nitrogen fertilizer. The yield of CP and EE, CA,NFE, and GE was mainly affected by nitrogen rates. The ADF yield increased was due to theincrement of the fresh and dry harvest biomass. Nitrogen applied as base fertilizer forsummer Zea mexicana can be harvested a higher biomass and improve the forage nutritivequality.展开更多
[Objective] The paper was to analyze the control effect of replacement cultivation of several high quality forages against Eupatorium adenophorum. [ Method] Five high quality forages including Lolium perenne, Dactylis...[Objective] The paper was to analyze the control effect of replacement cultivation of several high quality forages against Eupatorium adenophorum. [ Method] Five high quality forages including Lolium perenne, Dactylis glomerata, Setaria anceps, Trifolium repens and Medicago sativa were planted in the fields invaded by E. adenophorum, and their ecological adaptability and control effect against E. adenophorum were studied. [Result] Five kinds of forages could nor- mally grow at the local land. The indexes such as coverage, plant height, fresh weight of stems and leaves of S. anceps were the highest, and it showed very strong ecological adaptability as well as the best control effect on E. adenophorum, up to 97.85% and 93.81% at the first and second year, respectively, indicating good sustainable control effect. D. glomerata ranked the second place, of which the coverage after one year was 86% and the control effect on E. adenophorum was 89.68%. The other species showed poor control effect on E. adenophorum because of slow growth rate and heavily damage from companion weeds even they could establish dominant communities. [ Condusion] The paper provided reference for ecological control against E. adenophorum in local land and ecological restoration of invasive land.展开更多
Cell wall architecture plays a key role in stalk strength and forage digestibility.Lignin,cellulose,and hemicellulose are the three main components of plant cell walls,and they can impact stalk quality by affecting th...Cell wall architecture plays a key role in stalk strength and forage digestibility.Lignin,cellulose,and hemicellulose are the three main components of plant cell walls,and they can impact stalk quality by affecting the structure and strength of the cell wall.To explore cell wall development during secondary cell wall lignification in maize stalks,conventional and conditional genetic mapping were used to identify the dynamic quantitative trait loci(QTLs)of the cell wall components and digestibility traits during five growth stages after silking.Acid detergent lignin(ADL),cellulose(CEL),acid detergent fiber(ADF),neutral detergent fiber(NDF),and in vitro dry matter digestibility(IVDMD)were evaluated in a maize recombinant inbred line(RIL)population.ADL,CEL,ADF,and NDF gradually increased from 10 to 40 days after silking(DAS),and then they decreased.IVDMD initially decreased until 40 DAS,and then it increased slightly.Seventytwo QTLs were identified for the five traits,and each accounted for 3.48–24.04%of the phenotypic variation.Six QTL hotspots were found,and they were localized in the 1.08,2.04,2.07,7.03,8.05,and 9.03 bins of the maize genome.Within the interval of the pleiotropic QTL identified in bin 1.08 of the maize genome,six genes associated with cell wall component biosynthesis were identified as potential candidate genes for stalk strength as well as cell wall-related traits.In addition,26 conditional QTLs were detected in the five stages for all of the investigated traits.Twenty-two of the 26 conditional QTLs were found at 30 DAS conditioned using the values of 20 DAS,and at 50 DAS conditioned using the values of 40 DAS.These results indicated that cell wall-related traits are regulated by many genes,which are specifically expressed at different stages after silking.Simultaneous improvements in both forage digestibility and lodging resistance could be achieved by pyramiding multiple beneficial QTL alleles identified in this study.展开更多
This study was conducted to assess the fermentation and nutritive value of sorghum silage mixed with lablab at different proportions. The treatments consisted of a combination of two sorghum genotypes viz. “Brown mid...This study was conducted to assess the fermentation and nutritive value of sorghum silage mixed with lablab at different proportions. The treatments consisted of a combination of two sorghum genotypes viz. “Brown midrib” and “Brachytic dwarf” genotype of lablab and six population proportions viz. 150:0, 112.5:37.5, 75:75, 37.5:112.5, 0:150 and 150:150 × 10<sup>3</sup> plants·ha<sup>-1</sup> sorghum genotypes and lablab, respectively totalling to 12 numbers. Sorghum genotypes and lablab were grown as monocrop and in intercropping systems in the same field. Forage sorghum was harvested at the late-dough stage and lablab at 20% bloom. They were cut and chopped together and ensiled. Lablab in the silage mixture was its actual contribution to the total forage mixture. For each mixture, a 1-L glass jar (mini-silo) was filled with 500 g of fresh material and replicated four times. Forage in mini silos was fermented for 60 days at room temperature (25°C). Pre and post-silage dry samples were analysed for nutritive value and ensiled samples were analysed for fermentation characteristics. There was no significant difference in nutritive value between sorghum genotypes. The greatest impact of mixing lablab with sorghum genotypes was on crude protein (CP) and acid detergent fiber (ADF), but not on neutral detergent fiber (NDF). Across treatments, CP, ADF pH, lactic, and acetic acid concentrations increased as the proportion of LB was increased. The results indicated that lablab as an intercrop with sorghum for greater DM yield and forage and silage quality than respective monocrops.展开更多
Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leave...Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leaves with different nutritional quality.However,the importance of bamboo shoots to giant pandas,especially small and isolated populations,is not fully appreciated.Here,we explored whether mating time of giant pandas is shaped by bamboo shoot phenology.We also assessed the intensity of ongoing bamboo shoot harvesting by local communities in 42 giant panda reserves based on questionnaire surveys.Varying intensity and protection levels of bamboo shoot harvesting were found.From these data,we developed a priority ranking scheme of protection areas for this key food resource.Our study showed that pandas time their mating behavior to coincide with bamboo shoot phenology due to the high nutritional demands associated with mating and pregnancy.We also found that bamboo shoots were not well protected in many places.Liangshan,Daxiangling,and Xiaoxiangling,containing the most isolated panda populations,were identified as the areas with the most urgent need of protection.Furthermore,equal attention should be paid to the Qiong L-B population,as this region holds considerable potential to serve as a corridor between the Minshan and Qionglai populations.To address the challenges posed by bamboo shoot harvesting,we recommend establishing more practical bamboo shoot management policies,increasing public awareness of bamboo shoot protection,and providing alternative sources of income for local communities.展开更多
Understanding the relationship between dry matter yield and nutritive value throughout the growing season will help optimize the cutting intervals between harvests in alfalfa (Medicago sativa L.). The Ogallala Aquifer...Understanding the relationship between dry matter yield and nutritive value throughout the growing season will help optimize the cutting intervals between harvests in alfalfa (Medicago sativa L.). The Ogallala Aquifer is a very important water source when growing alfalfa in Southwest Kansas and unfortunately, the water level of the Ogallala Aquifer is shrinking. The objective of this study was to determine the optimum cutting interval that optimizes dry matter yield and nutritive values of alfalfa. Alfalfa was harvested with different cutting intervals, i.e., every 28, 35, 42 and 49 day, which was equivalent of 5, 4, 4, and 3 cuttings per year, respectively in 2013 and 2014. Based on 2-yr total yield, by delaying alfalfa harvest by 21 days, i.e., from every 28th day to 49th day, alfalfa yield increased by 2.25 Mg/ha whereas by 5.58 Mg/ha by delaying cutting intervals from every 28th day to 42nd day. Although harvesting alfalfa every 42nd day had the same cutting frequency as the 35th day treatment (i.e., 4 cuttings per year), the treatment harvesting every 42nd day had significantly higher alfalfa yield than 35th day cutting interval. Alfalfa yield increased by approximately 20% by delaying one week for harvesting alfalfa from 35th to 42nd day interval, based on dry matter yields of 2013 and 2014. As cutting interval increased from every 28th to 49th day, crude protein (CP) content decreased. In contrast to CP, acid detergent fiber and neutral detergent fiber increased as the cutting interval and stage of maturity increased in 2013 and 2014. The results suggest that alfalfa producers in Southwest Kansas possibly could reduce the cutting frequency from 5 to 4 per year. Cutting interval of every 42nd day between harvests appears to be the optimum when considered a dry matter yield and nutritive values in alfalfa.展开更多
Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei ...Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei Province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 (62.75 t ha^-1), Hom (62.72 t ha^-1), 86-266 (61.55 t ha^-1), German (61.44 t ha^-1) and Zhongmu 1 (61.18 t ha^-1), respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value (RFV) in both years while crude fiber had significant negative correlation with RFV and crude fiber.展开更多
Medicago sativa (lucerne) is a widely used perennial fodder crop and ranked amongst the highly nutritive fodders globally. This study assessed the nutritive value (i.e. CP % and TDN %) of four lucerne cultivars under ...Medicago sativa (lucerne) is a widely used perennial fodder crop and ranked amongst the highly nutritive fodders globally. This study assessed the nutritive value (i.e. CP % and TDN %) of four lucerne cultivars under two soil types at Bathurst Research Station. A random grid (quadrant) sampling method was used for sampling and samples were submitted to the laboratory for analysis to determine forage quality. Data collection was carried out by separating harvested biomass for each cultivar using clean packs, weighed and dried at 70˚C for 48 hours then crude protein (CP %) and Total Digestible Nutrients (TDN %) were determined. The results of the study showed that soil type (site) had a significant (P < 0.05) effect on the overall quality of dry matter produced. In soil 1 (S1) the overall CP % content was 11.48% while it was 19.03% in soil 2 (S2). Cultivar 3 (KKS 9911) was the least nutritive cultivar in site 1, while the same cultivar was the most nutritive cultivar in site 2 pertaining CP content. Soil type also significantly affected (P < 0.05) the overall total digestible nutrient (TDN %) content of different lucerne cultivars. In S1, C4 (WL 525) had the highest (P < 0.05) TDN content in comparison to the rest of the cultivars while in the same soil type C1 (SA Std.) had the least TDN content. The four tested lucerne cultivars generally produced highly nutritive lucerne in S2 while they produced less nutritive lucerne in relation to both CP and TDN content in S1.展开更多
Background:Soil and water salinity are increasing problems worldwide,causing significantly reduced crop yields.Alfalfa(Medicago sativa L.)is often listed as salt-sensitive,but field testing of improved cultivars is li...Background:Soil and water salinity are increasing problems worldwide,causing significantly reduced crop yields.Alfalfa(Medicago sativa L.)is often listed as salt-sensitive,but field testing of improved cultivars is limited.Forage systems and improved high-quality alfalfa varieties are needed to enable crop production under high salinity(HS)conditions.Methods:The objective of this study was to measure the yield and quality response of alfalfa to high saline conditions in the field and to document the relative saline tolerance of its varieties.HS irrigation water(electrical conductivity of water,or ECw 8.0–11.0 dS m−1)was applied to 33 nondormant alfalfa cultivars and were compared with low salinity(LS)treatments(ECw 0.5–1.2 dS m−1)over 4 years in a Mediterranean environment on a clay loam soil utilizing a split-plot design.Crops were harvested seven to eight times per year,and the forage quality was measured on selected harvests utilizing near-infrared spectroscopy.Results:The average yield loss due to HS treatment was 23.9%compared with LS treatment,but yields averaged 23.4 Mg ha−1 under HS over the 3 full years of production.This level of production is considered to be economically viable in this region.Differences in salinity tolerance between lines were identified in the field;individual cultivars lost 5%–35%of their LS yield when grown under HS conditions.Forage quality was significantly improved under HS versus LS conditions,but improvements were negatively correlated with biomass yield(R2>0.81),similar to responses observed in drought-stressed alfalfa.Conclusions:These yield results confirm greenhouse studies,indicating that alfalfa is highly salt tolerant once established in the field,with potential for further improvement with tolerant cultivars.Salinity tolerance should be chosen based on total biomass yield as well as on the salinity tolerance index(HS yield relative to LS yield).Agronomic practices to mitigate salinity and sodicity are critical,along with improved cultivars.展开更多
Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes...Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes,nutrient uptake,and stand growth.Additionally,the maturity stage at harvest can significantly impact both hay yield and quality.Thus,this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield,nutritive value,and the overall profitability of commercially cultivated alfalfa.Methods:Two conventional and three lower-lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought,rainfed,and irrigation conditions in 2020 in Manhattan,Kansas,USA.The dry matter yield(DMY)and forage nutritive value were evaluated at late bud,early flowering,and 7 days after early flowering stages,respectively.Results:DMY varied with production year,soil water availability,and growth stages,with drought conditions causing a decline in DMY of 5%to 38%in the second production year.Water conditions and maturity stages influenced crude protein(CP)and in vitro dry matter digestibility(IVDMD).Higher soil moisture and advancing maturity stages negatively impacted CP,IVDMD,and relative forage quality.The study revealed net profit margins of 62%,64%,and 52%for drought-prone,rainfed,and irrigated production,respectively.Conclusions:Harvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of alfalfa.The yield-quality trade-off differed under drought and irrigation,with early harvesting leading to lower yields but higher protein content and digestibility.The study findings provide potential guidance for improving alfalfa hay yield,quality,and profitability.展开更多
Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their ...Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their nutritive value:Lolium perenne(LP);L.perenne+Trifolium repens(LP+TR);and a multispecies sward containing grasses,legumes and herbs(MSS).Farmlets were stocked with beef steers(2.5 livestock units ha−1),grazed on a 1 ha scale to 6 cm(MSS)and 4 cm(LP and LP+TR)residuals.Results:A greater ash concentration was found in MSS than LP(84 vs.75 g kg−1 DM).Both LP+TR and MSS had higher crude protein and lower neutral detergent fibre concentrations than LP.The relative ranking of water soluble carbohydrate and dry matter(DM)concentration was LP>LP+TR>MSS.Despite the leaf component of the LP farmlet contributing more to herbage DM,the organic matter digestibilities of the swards were similar.Conclusions:The MSS and LP+TR farmlets achieved similar forage quality under intensive grazing to LP.However,it is worth noting that MSS had a higher concentration of acid detergent lignin,which can negatively impact digestibility.Further investigation is needed to determine optimal grazing management practices that can minimise the effects of higher lignin concentration on digestibility in multispecies swards.展开更多
Forage yield is the fundamental ecosystem service of grasslands.While the quantitative responses of forage yield to nitrogen(N)enrichment are well known,its qualitative responses remain unclear.Even less known is the ...Forage yield is the fundamental ecosystem service of grasslands.While the quantitative responses of forage yield to nitrogen(N)enrichment are well known,its qualitative responses remain unclear.Even less known is the relative contribution of changes in community composition to the quality of the yield at the community level.We examined the quantitative and qualitative responses of forage yield at both plant functional group and community levels with factorial treatments of N addition and mowing in a temperate steppe.Nitrogen addition significantly enhanced the community-level yield by favoring the growth of rhizomatous grass.Mowing tended to mediate the impacts of N addition on the yield.Nitrogen addition increased the concentrations of crude protein and crude fat in forage at the community level.Neither the main effects of mowing nor its interactive effects with N addition affected forage quality.The N-induced shifts in plant species composition significantly contributed to the effects of N addition on forage quality at the community level.Our results suggest that mowing wound weaken the positive effects of N deposition on the quantity but not the quality of forage yield.Changes in plant community composition are important in driving the qualitative responses of yield to N deposition.展开更多
基金supported by the National Natural Science Foundation of China (31971755)the Beijing Municiple Natural Science Foundation (6192011) of China。
文摘Alfalfa (Medicago sativa L.) is the most widely cultivated perennial leguminous forage crop woldwide.Micro RNA156 (miR156) precursor genes from dicotyledonous species are reportedly useful for improving alfalfa plant architecture and abiotic stress resistance.However,there has been no report on whether a miR156 precursor gene from a monocotyledonous species functions in alfalfa.We introduced two tandem precursor genes of miR156,rice Osa-MIR156b and Osa-MIR156c (Osa-MIR156bc),into alfalfa.The expression of miR156 in the transgenic (TG) alfalfa was significantly elevated.Compared to wild-type plants,the TG plants overexpressing miR156 had more branches and leaves and showed improved salt and drought tolerance.Overexpression of miR156 slightly reduced plant height,but the biomass yield of TG plants grown in flowerpots was still increased.Forage quality of TG plants was markedly improved by reduction of acid detergent lignin (ADL) content and increase in crude protein content.The expression of the putative miR156 target genes Ms SPL6,Ms SPL12,and Ms SPL13 in TG plants was repressed by miR156overexpression,and that of all tested Ms SPLs would be sharply increased under drought or salt stress.RNA sequencing revealed that overexpression of miR156 affected the expression of genes associated with abiotic stress resistance and plant development in multiple pathways.This first report of overexpression of monocot miR156 precursors in alfalfa sheds light on the function of mi RNA156 precursors from the monocot species rice that could be used for genetic improvement of the dicot forage crop alfalfa.
文摘The nutritional value of kudzu (Pueraria lobata) was evaluated as a potential animal feed. Randomly selected samples from natural habitats with Jacksonville area (Alabama, USA) were utilized in the study. Kudzu leaves showed significantly higher dry matter and crude protein content than the stems;whereas, ADF fiber was significantly lower in the leaves. However, NDF and total digestible nutrients (TDN) were similar in the leaves and the stems. The leaf part of kudzu was especially rich in CP (24.46%) and met the requirements and recommendations for most ruminants. The TDN value for kudzu stem is 55.99%, which falls below but within the recommended range. Macronutrients concentration between the stem and leaf of kudzu, nitrogen, calcium, and magnesium showed a significantly higher in the leaf than the stem. However, phosphorous was similar in concentration in the stem and the leaf, and potassium was higher in the stem. In regard to the micronutrients, the only significant difference between the leaf and the stem was iron. However, iron, manganese, zinc, and copper were all above the recommended concentrations by the National Research Council. In general, kudzu can be considered a good source for animal feed, especially the leaf, which shows a higher value in most of the determined criteria in comparison to what was recommended by the National Research Council. This should provide a new outlook to kudzu, which has been considered a noxious weed and help in the utilization of kudzu in a positive way in the southern region of the US.
基金supported by grants from the National Key Basic Research Program of China(No. 2011CB100803)
文摘Thirty lactating Holstein cows were used to investigate the effects of different forages quality on milk fatty acids(FA) profiles and production. The cows were assigned to 3 dietary treatments(n = 10 per treatment) in a randomized block design with 3 repeated measures. They were fed the experimental diets for 90 d with 3 days of collection of samples for analysis at about 27 d intervals(samples were collected on days 28,29,30, 58, 59, 60.88, 89 and 90). The treatments were(DM basis): 1) mixed forages diet(MF) consisting of 3.7% Chinese wild rye, 26.7% corn silage and 23.4% alfalfa hay; 2) corn stalk diet 1(CS1) where corn stalk was used to formulate a similar chemical nutrient level to MF; 3) corn stalk diet 2(CS2) which used corn stalk to formulate a similar forage level to MF for the diet. Dry matter intake and BW were similar between treatments, but daily milk yield, milk fat and protein yield decreased(P < 0.05)in CS1 and CS2 compared with MF, with CS2 being the lowest(P < 0.05). In total FA of milk, the compositions of C18:1 c9, C18:3 and unsaturated FA increased(P < 0.05) in CS1 and CS2 compared with MF,and C18:0 and trans-C18:1 were trended to increase(P < 0.10), but C4:0-C16:0 were decreased(P < 0.05).Compared with cows fed CS2, cows receiving CS1 increased the compositions of C4:0 to C12:0 and C18:2(P < 0.05). The results suggests feeding corn stalk could produce a greater proportion of unsaturated fatty acid(UFA) in milk fat without resulting in milk fat depression(MFD) in mid lactation cows, but simply increasing the ratio of concentrate in low forages diets is not an effective way to increase milk fat synthesis and milk production.
基金the Agricultural Research Center,Giza,Egypt,and the Taif University Researchers Supporting Project(TURSP-2020/111),Taif University,Taif,Saudi Arabia for the technical and financial support to this research。
文摘Among the crop production factors,preceding crop and tillage management affect the sustainable use of soil resources and ultimately crop growth and productivity.This study aimed at investigating the impact of preceding winter crops(grass or legume)and different tillage systems on forage yield,quality and nutritive values of three summer grass(Sudan grass,pearl millet and teosinte)and two legume forage crops(cowpea and guar)under arid conditions.The results exhibited that growing forage crops after legumes(as berseem clover)produced the highest fresh and dry forage yields and quality attributes compared with grasses(as wheat)with the exception of crude fiber content,which was decreased.Moreover,tillage practices showed positive impact on forage yields and quality attributes.The maximum forage yields and quality parameters were recorded under conventional tillage(CT)practice compared with reduced tillage(RT)and no-tillage(NT)systems.Among the evaluated crops,the highest yields of fresh forage,dry forage,crude fiber,crude protein and total digestible nutrient were exhibited by grass forage crops(Sudan grass,pearl millet and teosinte),whereas the highest crude protein content and the digestible energy values were produced by legume forage crops(cowpea and guar).The maximum fresh forage,dry forage,crude fiber,crude protein,total digestible nutrient and digestible crude protein yields were produced by pearl millet followed by Sudan grass under CT and RT after berseem clover.The highest net return was recorded by sowing pearl millet after berseem clover and applying CT followed by RT practices,which could be recommended for the commercial production.Moreover,it could be assumed that the combination of growing grass forage crops after legume crops under CT or RT systems could enhance forage crop yield and quality with an improvement in soil properties for sustainable agriculture with low cost and the highest net income.
基金National Key Research and Development Program of China(2017YFD0200808)Seed Science and Technology Major Special Program of Tianjin(18ZXZYNC00100)+1 种基金Scientific Research Program(Natural Science)of Tianjin Education Committee(2019KJ039)Graduate Research Innovation Program of Tianjin(2020YJSS128).
文摘In order to investigate the effects of meteorological factors on rape overwintering ability,forage yield and quality of rape in the North China plain,Brassia campestris L.and Brassica napus L.were used in this study.The results showed that compared with the B.napus L.varieties,the growth period of B.campestris L.was shortened by 10-15 d,the overwintering rate(WR)increased by 50.6%,and the density after winter(PD)increased by 41.5%.The fresh forage yield(FFY)and dry forage yield(DFY)of the B.campestris L.type significantly increased by 40.9%and 38.1%compared with the B.napus L.type.,respectively,while the forage quality of the B.napus L.type rape was significantly better than that of the B.campestris L.type.Compared with the B.campestris L.type,the crude protein(CP),fat,ash and total fatty acid(TFA)contents of the B.napus L.type of rape increased by 27.6%,42.9%,23.9%and 52.3%,respectively,and the milk productivity(HM),relative forage value(RFV)and relative forage quality(RFQ)increased by 14.0%,16.2%and 42.1%,respectively.The light and heat resources before wintering increased the WR and PD(P<0.05),and were positively correlated with FFY and DFY(P>0.05),and lower temperature during the wintering period led to lower WR(P<0.01).The light and heat resources during the overwintering period and after regreening were negatively correlated with FFY and DFY(P>0.05).The contents of CP,fat and TFA of rape had an extremely significant negative correlation with the temperature and sunshine hours before wintering,but an extremely significant positive correlation with the temperature during the wintering period and after regreening,as well as the sunshine hours and rainfall during the wintering period;and HM had an extremely significant positive correlation with the temperature,sunshine hours and rainfall during the wintering period,while RFV and RFQ were only extremely significantly positively correlated with the maximum temperature and rainfall.In summary,in the North China Plain,for autumn sowing rape,the B.campestris L.type can be selected to improve the wintering rate,and the B.napus L.type should be the main choice to improve the forage quality of rape.Therefore,the B.napus L.variety HYZ62 can be selected for autumn sowing in the North China Plain.
基金financially supported by the National Natural Science Foundation of China(30100108)the National Key Technologies R&D Program in Tenth Five Plan by the Ministry of Science and Technology,China(2002BA51A13).
文摘A pool experiment was carried out to study the effects of different nitrogen applicationstrategies (rates and stages of nitrogen application) on yield and forage nutritivequality of Zea mexicana cultivated in summer, 2002. In the whole growing stage, its stemwas clipped three times at the height of 25cm when it was 110cm high (H1, H2 and H3 standfor the first, second and third harvest stage, respectively). Six indexes includingcrude protein (CP), ether extract (EE), nitrogen free extract (NFE), acid detergentfiber (ADF), crude ash (CA), and general energy (GE) were employed to evaluate the foragenutritive value. The results showed that the content of CP and EE increased but thecontent of CA and ADF decreased under the two nitrogen rates (High-rate N, 600kgha-1;Mid-rate N, 300kgha-1). The fresh and dry harvest biomass of the whole plants on H1 andthose of the leaves on H2 were also improved. But the stalks on H2 and the whole plantson H3 were affected mainly by dressing nitrogen fertilizer. The yield of CP and EE, CA,NFE, and GE was mainly affected by nitrogen rates. The ADF yield increased was due to theincrement of the fresh and dry harvest biomass. Nitrogen applied as base fertilizer forsummer Zea mexicana can be harvested a higher biomass and improve the forage nutritivequality.
基金Supported by Industrial Technology Innovation Alliance Program of Sichuan Province(2010Z00024)
文摘[Objective] The paper was to analyze the control effect of replacement cultivation of several high quality forages against Eupatorium adenophorum. [ Method] Five high quality forages including Lolium perenne, Dactylis glomerata, Setaria anceps, Trifolium repens and Medicago sativa were planted in the fields invaded by E. adenophorum, and their ecological adaptability and control effect against E. adenophorum were studied. [Result] Five kinds of forages could nor- mally grow at the local land. The indexes such as coverage, plant height, fresh weight of stems and leaves of S. anceps were the highest, and it showed very strong ecological adaptability as well as the best control effect on E. adenophorum, up to 97.85% and 93.81% at the first and second year, respectively, indicating good sustainable control effect. D. glomerata ranked the second place, of which the coverage after one year was 86% and the control effect on E. adenophorum was 89.68%. The other species showed poor control effect on E. adenophorum because of slow growth rate and heavily damage from companion weeds even they could establish dominant communities. [ Condusion] The paper provided reference for ecological control against E. adenophorum in local land and ecological restoration of invasive land.
基金the National Natural Science Foundation of China(31801367)the National Key Research and Development Program of China(2016YFD0101200)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences.
文摘Cell wall architecture plays a key role in stalk strength and forage digestibility.Lignin,cellulose,and hemicellulose are the three main components of plant cell walls,and they can impact stalk quality by affecting the structure and strength of the cell wall.To explore cell wall development during secondary cell wall lignification in maize stalks,conventional and conditional genetic mapping were used to identify the dynamic quantitative trait loci(QTLs)of the cell wall components and digestibility traits during five growth stages after silking.Acid detergent lignin(ADL),cellulose(CEL),acid detergent fiber(ADF),neutral detergent fiber(NDF),and in vitro dry matter digestibility(IVDMD)were evaluated in a maize recombinant inbred line(RIL)population.ADL,CEL,ADF,and NDF gradually increased from 10 to 40 days after silking(DAS),and then they decreased.IVDMD initially decreased until 40 DAS,and then it increased slightly.Seventytwo QTLs were identified for the five traits,and each accounted for 3.48–24.04%of the phenotypic variation.Six QTL hotspots were found,and they were localized in the 1.08,2.04,2.07,7.03,8.05,and 9.03 bins of the maize genome.Within the interval of the pleiotropic QTL identified in bin 1.08 of the maize genome,six genes associated with cell wall component biosynthesis were identified as potential candidate genes for stalk strength as well as cell wall-related traits.In addition,26 conditional QTLs were detected in the five stages for all of the investigated traits.Twenty-two of the 26 conditional QTLs were found at 30 DAS conditioned using the values of 20 DAS,and at 50 DAS conditioned using the values of 40 DAS.These results indicated that cell wall-related traits are regulated by many genes,which are specifically expressed at different stages after silking.Simultaneous improvements in both forage digestibility and lodging resistance could be achieved by pyramiding multiple beneficial QTL alleles identified in this study.
文摘This study was conducted to assess the fermentation and nutritive value of sorghum silage mixed with lablab at different proportions. The treatments consisted of a combination of two sorghum genotypes viz. “Brown midrib” and “Brachytic dwarf” genotype of lablab and six population proportions viz. 150:0, 112.5:37.5, 75:75, 37.5:112.5, 0:150 and 150:150 × 10<sup>3</sup> plants·ha<sup>-1</sup> sorghum genotypes and lablab, respectively totalling to 12 numbers. Sorghum genotypes and lablab were grown as monocrop and in intercropping systems in the same field. Forage sorghum was harvested at the late-dough stage and lablab at 20% bloom. They were cut and chopped together and ensiled. Lablab in the silage mixture was its actual contribution to the total forage mixture. For each mixture, a 1-L glass jar (mini-silo) was filled with 500 g of fresh material and replicated four times. Forage in mini silos was fermented for 60 days at room temperature (25°C). Pre and post-silage dry samples were analysed for nutritive value and ensiled samples were analysed for fermentation characteristics. There was no significant difference in nutritive value between sorghum genotypes. The greatest impact of mixing lablab with sorghum genotypes was on crude protein (CP) and acid detergent fiber (ADF), but not on neutral detergent fiber (NDF). Across treatments, CP, ADF pH, lactic, and acetic acid concentrations increased as the proportion of LB was increased. The results indicated that lablab as an intercrop with sorghum for greater DM yield and forage and silage quality than respective monocrops.
基金supported by the National Natural Science Foundation of China (32071496,32225033)Chinese Academy of Sciences (XDA23080500,QYZDB-SSW-SMC047)。
文摘Animals that live in seasonal environments adjust their reproduction cycle to optimize seasonal forage quality.Giant pandas(Ailuropoda melanoleuca)are seasonal altitudinal migrants that feed on bamboo shoots and leaves with different nutritional quality.However,the importance of bamboo shoots to giant pandas,especially small and isolated populations,is not fully appreciated.Here,we explored whether mating time of giant pandas is shaped by bamboo shoot phenology.We also assessed the intensity of ongoing bamboo shoot harvesting by local communities in 42 giant panda reserves based on questionnaire surveys.Varying intensity and protection levels of bamboo shoot harvesting were found.From these data,we developed a priority ranking scheme of protection areas for this key food resource.Our study showed that pandas time their mating behavior to coincide with bamboo shoot phenology due to the high nutritional demands associated with mating and pregnancy.We also found that bamboo shoots were not well protected in many places.Liangshan,Daxiangling,and Xiaoxiangling,containing the most isolated panda populations,were identified as the areas with the most urgent need of protection.Furthermore,equal attention should be paid to the Qiong L-B population,as this region holds considerable potential to serve as a corridor between the Minshan and Qionglai populations.To address the challenges posed by bamboo shoot harvesting,we recommend establishing more practical bamboo shoot management policies,increasing public awareness of bamboo shoot protection,and providing alternative sources of income for local communities.
文摘Understanding the relationship between dry matter yield and nutritive value throughout the growing season will help optimize the cutting intervals between harvests in alfalfa (Medicago sativa L.). The Ogallala Aquifer is a very important water source when growing alfalfa in Southwest Kansas and unfortunately, the water level of the Ogallala Aquifer is shrinking. The objective of this study was to determine the optimum cutting interval that optimizes dry matter yield and nutritive values of alfalfa. Alfalfa was harvested with different cutting intervals, i.e., every 28, 35, 42 and 49 day, which was equivalent of 5, 4, 4, and 3 cuttings per year, respectively in 2013 and 2014. Based on 2-yr total yield, by delaying alfalfa harvest by 21 days, i.e., from every 28th day to 49th day, alfalfa yield increased by 2.25 Mg/ha whereas by 5.58 Mg/ha by delaying cutting intervals from every 28th day to 42nd day. Although harvesting alfalfa every 42nd day had the same cutting frequency as the 35th day treatment (i.e., 4 cuttings per year), the treatment harvesting every 42nd day had significantly higher alfalfa yield than 35th day cutting interval. Alfalfa yield increased by approximately 20% by delaying one week for harvesting alfalfa from 35th to 42nd day interval, based on dry matter yields of 2013 and 2014. As cutting interval increased from every 28th to 49th day, crude protein (CP) content decreased. In contrast to CP, acid detergent fiber and neutral detergent fiber increased as the cutting interval and stage of maturity increased in 2013 and 2014. The results suggest that alfalfa producers in Southwest Kansas possibly could reduce the cutting frequency from 5 to 4 per year. Cutting interval of every 42nd day between harvests appears to be the optimum when considered a dry matter yield and nutritive values in alfalfa.
基金supported by the Earmarked Fund for the Modern Agro-Industry Technology Research System,China(CARS-35)
文摘Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei Province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 (62.75 t ha^-1), Hom (62.72 t ha^-1), 86-266 (61.55 t ha^-1), German (61.44 t ha^-1) and Zhongmu 1 (61.18 t ha^-1), respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value (RFV) in both years while crude fiber had significant negative correlation with RFV and crude fiber.
文摘Medicago sativa (lucerne) is a widely used perennial fodder crop and ranked amongst the highly nutritive fodders globally. This study assessed the nutritive value (i.e. CP % and TDN %) of four lucerne cultivars under two soil types at Bathurst Research Station. A random grid (quadrant) sampling method was used for sampling and samples were submitted to the laboratory for analysis to determine forage quality. Data collection was carried out by separating harvested biomass for each cultivar using clean packs, weighed and dried at 70˚C for 48 hours then crude protein (CP %) and Total Digestible Nutrients (TDN %) were determined. The results of the study showed that soil type (site) had a significant (P < 0.05) effect on the overall quality of dry matter produced. In soil 1 (S1) the overall CP % content was 11.48% while it was 19.03% in soil 2 (S2). Cultivar 3 (KKS 9911) was the least nutritive cultivar in site 1, while the same cultivar was the most nutritive cultivar in site 2 pertaining CP content. Soil type also significantly affected (P < 0.05) the overall total digestible nutrient (TDN %) content of different lucerne cultivars. In S1, C4 (WL 525) had the highest (P < 0.05) TDN content in comparison to the rest of the cultivars while in the same soil type C1 (SA Std.) had the least TDN content. The four tested lucerne cultivars generally produced highly nutritive lucerne in S2 while they produced less nutritive lucerne in relation to both CP and TDN content in S1.
基金USDA NIFA,Grant/Award Number:CA-D-PLS-2482-CGUS Alfalfa Farmer Research Initiative(National Alfalfa&Forage Alliance)+1 种基金California State University Agricultural Research Institute(CSU-ARI),Grant/Award Number:17-01-002California Crop Improvement Association。
文摘Background:Soil and water salinity are increasing problems worldwide,causing significantly reduced crop yields.Alfalfa(Medicago sativa L.)is often listed as salt-sensitive,but field testing of improved cultivars is limited.Forage systems and improved high-quality alfalfa varieties are needed to enable crop production under high salinity(HS)conditions.Methods:The objective of this study was to measure the yield and quality response of alfalfa to high saline conditions in the field and to document the relative saline tolerance of its varieties.HS irrigation water(electrical conductivity of water,or ECw 8.0–11.0 dS m−1)was applied to 33 nondormant alfalfa cultivars and were compared with low salinity(LS)treatments(ECw 0.5–1.2 dS m−1)over 4 years in a Mediterranean environment on a clay loam soil utilizing a split-plot design.Crops were harvested seven to eight times per year,and the forage quality was measured on selected harvests utilizing near-infrared spectroscopy.Results:The average yield loss due to HS treatment was 23.9%compared with LS treatment,but yields averaged 23.4 Mg ha−1 under HS over the 3 full years of production.This level of production is considered to be economically viable in this region.Differences in salinity tolerance between lines were identified in the field;individual cultivars lost 5%–35%of their LS yield when grown under HS conditions.Forage quality was significantly improved under HS versus LS conditions,but improvements were negatively correlated with biomass yield(R2>0.81),similar to responses observed in drought-stressed alfalfa.Conclusions:These yield results confirm greenhouse studies,indicating that alfalfa is highly salt tolerant once established in the field,with potential for further improvement with tolerant cultivars.Salinity tolerance should be chosen based on total biomass yield as well as on the salinity tolerance index(HS yield relative to LS yield).Agronomic practices to mitigate salinity and sodicity are critical,along with improved cultivars.
基金US Department of Agriculture,National Institute of Food and Agriculture,Grant/Award Number:2019-70005-30238。
文摘Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United States.Soil moisture critically influences alfalfa's yield and quality,affecting its physiological processes,nutrient uptake,and stand growth.Additionally,the maturity stage at harvest can significantly impact both hay yield and quality.Thus,this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield,nutritive value,and the overall profitability of commercially cultivated alfalfa.Methods:Two conventional and three lower-lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought,rainfed,and irrigation conditions in 2020 in Manhattan,Kansas,USA.The dry matter yield(DMY)and forage nutritive value were evaluated at late bud,early flowering,and 7 days after early flowering stages,respectively.Results:DMY varied with production year,soil water availability,and growth stages,with drought conditions causing a decline in DMY of 5%to 38%in the second production year.Water conditions and maturity stages influenced crude protein(CP)and in vitro dry matter digestibility(IVDMD).Higher soil moisture and advancing maturity stages negatively impacted CP,IVDMD,and relative forage quality.The study revealed net profit margins of 62%,64%,and 52%for drought-prone,rainfed,and irrigated production,respectively.Conclusions:Harvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of alfalfa.The yield-quality trade-off differed under drought and irrigation,with early harvesting leading to lower yields but higher protein content and digestibility.The study findings provide potential guidance for improving alfalfa hay yield,quality,and profitability.
基金Department of Agriculture,Food and the Marine Research,Irish Government,Grant/Award Number:RSF 17/S/267:SMARTSWARD。
文摘Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their nutritive value:Lolium perenne(LP);L.perenne+Trifolium repens(LP+TR);and a multispecies sward containing grasses,legumes and herbs(MSS).Farmlets were stocked with beef steers(2.5 livestock units ha−1),grazed on a 1 ha scale to 6 cm(MSS)and 4 cm(LP and LP+TR)residuals.Results:A greater ash concentration was found in MSS than LP(84 vs.75 g kg−1 DM).Both LP+TR and MSS had higher crude protein and lower neutral detergent fibre concentrations than LP.The relative ranking of water soluble carbohydrate and dry matter(DM)concentration was LP>LP+TR>MSS.Despite the leaf component of the LP farmlet contributing more to herbage DM,the organic matter digestibilities of the swards were similar.Conclusions:The MSS and LP+TR farmlets achieved similar forage quality under intensive grazing to LP.However,it is worth noting that MSS had a higher concentration of acid detergent lignin,which can negatively impact digestibility.Further investigation is needed to determine optimal grazing management practices that can minimise the effects of higher lignin concentration on digestibility in multispecies swards.
基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDA23070103)National Natural Science Foundation of China(31770503,31822006,and 31901141)+2 种基金K.C.Wong Education Foundation(GJTD-2019-10)Liaoning Revitalizing Talents Program(XLYC1807061)Youth Innovation Promotion Association CAS(Y201832).
文摘Forage yield is the fundamental ecosystem service of grasslands.While the quantitative responses of forage yield to nitrogen(N)enrichment are well known,its qualitative responses remain unclear.Even less known is the relative contribution of changes in community composition to the quality of the yield at the community level.We examined the quantitative and qualitative responses of forage yield at both plant functional group and community levels with factorial treatments of N addition and mowing in a temperate steppe.Nitrogen addition significantly enhanced the community-level yield by favoring the growth of rhizomatous grass.Mowing tended to mediate the impacts of N addition on the yield.Nitrogen addition increased the concentrations of crude protein and crude fat in forage at the community level.Neither the main effects of mowing nor its interactive effects with N addition affected forage quality.The N-induced shifts in plant species composition significantly contributed to the effects of N addition on forage quality at the community level.Our results suggest that mowing wound weaken the positive effects of N deposition on the quantity but not the quality of forage yield.Changes in plant community composition are important in driving the qualitative responses of yield to N deposition.