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By determining and analyzing water soluble salt,organic matter,pH value,total N,hydrolytic N,total P,available P,total K and available K of each soil layer in alfalfa fields with different growth years, the effect of alfalfa with different growth years on the interannual variability and vertical distribution of soil fertility in saline-alkali land in western Songnen plain. The results showed that growing alfalfa could decrease soil pH value and water soluble salt content effectively. The contents of total N, hydrolytic N, total P and available K of each soil layer in alfalfa field had all declined in the seeding year. The contents of organic matter,total P, total N and hydrolytic N were all increased in alfalfa field sown for more than 2 years. The contents of available P in the CK and each alfalfa field tend to decrease progressively with soil layer’s decline, and the content of available K was highest in the surface layer.
This study examined the litter of degraded desert steppe among different years of enclosure and the unenclosed grassland in Yanchi. It showed that the litter accumulation reached a maximum in September and October then declined with the time increasing. The litter decomposition rate was gradually decreased with the time. The litter decomposition rates of the enclosed grassland were higher than that of the unenclosed. With time increasing, natural water holding rates of litter reached a maximum and then declined gradually. Both the total nitrogen content of litter and the total phosphor content of litter of the enclosed grassland were lower than that of the unenclosed. The total kalium content of litter reached a minimum at the 5th year.
Through field investigation of Hulunbeier sandy meadow grassland which was roller compacted by vehicle and relevant samples by laboratory analysis, the research was made on grassland vegetation and soil changes caused by the vehicles rolling.The results showed that the grassland underground biomass, soil organic matter, soil total nitrogen, soil available nitrogen and phosphorus significantly decreased with increased of the roller compacted extent which resulted in depth rut(P0.05), available K increased firstly and then decreased. Vehicle rolling destructed above-ground plant communities and roots, significantly reduced in below-ground biomass and soil nutrients, and promoted wind erosion which led to the loss of topsoil. Therefore, control of the vehicle rolling and protection of grassland vegetation and topsoil are extremely important to prevent soil erosion break formation caused by vehicle rolling and to combat grassland desertification.
Festuca sinensis, a good quality and cold tolerant forage in alpine region of China, was studied to explore the effect of two systemic fungicides on fungal endophyte of F.sinensis at different concentrations and times. Thiophanate-methyl (TM) and difenoconazole (D) had five concentrations and four distinct times respectively. The result of germination experiment indicated that 8 h was the most reasonable. Meanwhile, 500, 300-fold dilution TM and 3000, 1 000-fold dilution D were considered to be effective treatments for a next experiment with the 8 h. The result revealed that the order of endophyte infection of seedling was: 3 000 D500 TM300 TM1 000 D; the order of germination rate of seedling was: 300 TM500 TM3 000 D1 000 D. The sterilization of 300 and 500-fold dilution TM was significant (P0.05) and had no adverse effect on germination rate,endophyte infection of seedling was reduced from 98% to 7% and 10%. The 8 h treatment of 1 000 and 3 000-fold dilution D reduced germination rate significantly (P0.05) from 79% to 54% and 63%, and at the same time, endophyte infection was reduced significantly (P0.05) from 98% to 5% and 30%. Therefore, the solution of 300-500-fold dilution thiophanate-methyl treated seeds in 8 h was the best way to eliminate fungal endophyte of F.sinensis.
Embellisia astragali is a stong and virulent pathogen that develops within milk vetch (Astragalus adsurgens).So far no research had been conducted on chemical controlling for this serious disease. This study assessed the efficacy of five fungicides on E.astragalus through inhibitory tests for colonal growth, spore germination and hypha elongation. The results showed that five tested fungicides all had reflected the colonal growth, spore germination and hypha elongation of E.astragalus partly. The order of concentration for 50% of maximal effect (EC50) was chlorothalonilmetalaxylmancozebThiophanate-methyltriadimefon within above 3 tests, the EC50 of chlorothalonil on colonal growth, spore germination and hypha elongation was 0.028, 0.03 and 0.04 g·L-1 respectively, the EC50 of triadimefon was 0.46, 0.48 and 0.21 g·L-1 respectively.
A pot experiment was conducted to determine the effect of five shading conditions (shading rates of 0, 60%, 80%, 85% and 93%) respectively on morphological and physiological indexes of Oplismenus undulatifolius to study its shade-endurance capacity. The results showed that with the shading intensity increased, various morphological index (main stem length, new leaves number and tillers number) of O.undulatifolius were increased first and then decreased, while the relative water content of leaves gradually improved. Under the shading rate of 80%, the chlorophyll content reached its peak, the ratio of chlorophyll a/b was less than that under other environments, and the free proline content accumulated rapidly. In addition, with the shade the extension of time, chlorophyll content and ratio of chlorophyll a/b were decreased, meanwhile the accumulation process of free proline content became inapparent under the same shading treatment. According to the data, O.undulatifolius is suitable to cultivate under 80% shading condition in the higher canopy density under the trees or beside the buildings as a shadow tolerance groundcover plant.
In order to broaden the application range of reclaimed water in urban greenbelt, a pot experiment was conducted, reclaimed water was used in greenbelt irrigation test of white clover and alfalfa. The changes of photosynthetic characteristic and chlorophyll content under reclaimed water irrigation have been studied. The results showed that reclaimed water irrigation can improve photosynthetic indices in a certain period of time and to some extent. Later, reclaimed water for white clover irrigation, the photosynthetic rate (Pn), transpiration rate (Tr), conductance to H2O (Gs) and CO2 concentration (Ci) under the irrigation test is significantly higher than that under running water irrigation. Two plants species’ changes of Tr, Pn, intercellular Ci are closely related with Gs. There is no significant difference in photochemical efficiency (Fv/Fm) and chlorophyll content between running water and reclaimed water. In short, reclaimed water irrigation does not cause damage to white clover and alfalfa, and has a certain role in promotion.
In this study golf landscape was divided into hard and soft landscape according to golf course landscape classification, three theories of landscape study, the golf course landscape AHP evaluation model was built initially using AHP method, and the parkland golf course plants landscape AHP evaluation model was also constructed, forming indictor type layer, landscape system layer and landscape evaluation index layer, which had the combination of quantitative and qualitative research, scientific selection of evaluation and setting of reasonable weight.
Effects of different NaCl concentration(0,17,51,85,136,204 and 272 mmol·L-1)on creeping bentgrass (Agrostis soionifera) seed germination rate, callus formation, growth, plantlet regeneration and POD and SOD activities of regenerated seedlings were studied using creeping bentgrass seeds. The results showed that creeping bentgrass germination rate, callus induction rate and differentiation rate and seedling regeneration rate decreased with NaCl concentration increasing gradually. When NaCl concentration was above 272 mmol·L-1,seed germination was inhibited completely. When NaCl concentration was 204 mmol·L-1, calluses were not able to grow at all. Under salt stress, SOD activity of creeping bentgrass regenerated seedlings rose to the maximum value of 83 U·g-1 and then declined. Changes of POD activity were similar to SOD activity.
Pot experiments were conducted to study the growth of three herbs (Spodiopogon sibiricus, Penniseturn alopecuroides, Panicum virgatum) on Zn-polluted soil with five concentrations (62.5, 125, 250, 500, 1 000 mg·kg-1). Physiological indices and Zn concentration in the three herbs were measured to assess the tolerance and accumulation for Zn pollution. Aboveground biomass of P.virgatum reduced by 68.2% in Zn treatment 1 000 mg·kg-1 and belowground biomass reduced by 70.5% compared with control. The aboveground biomass and belowground biomass of P.alopecuroides reduced by 33.7% and 69.7% respectively. The biomass of S.sibiricus has no significant difference compared with control, the tolerance was S.sibiricusP.alopecuroidesP.virgatum. The physiological indices of the three herbs had significant change, and the change was S.sibiricusP.alopecuroidesP.virgatum. The accumulation of three herbs for Zn were P.alopecuroidesS.sibiricusP.virgatum. For P.alopecuroides, the accumulation of aboveground and belowground reached the highest value of 156.38 mg·kg-1 and 303.51 mg·kg-1 in the treatment 1 000 mg·kg-1.
In this paper, taking Ocimum basilicum ‘purple ruffles’ and O.cimun gratissimum seedlings at different anthocyanin contents in leaves of two varieties as test material, effects of anthocyanin in leaves on chlorophyll fluorescence and light energy distribution in leaves of O.basilicum seedlings exposed to low (200 μmol·m-2·s-1) and high (1 000 μmol·m-2·s-1) light intensity after low temperature at 4 ℃ in dark for 3 hours were studied. The results showed that fluorescence parameters in leaves of O.gratissimum seedlings at low temperature were essentially unchanged under low light. The quantum yield of photochemistry (YPSⅡ) in leaves of O.basilicum ‘purple ruffles’ seedlings under low light after low temperature was lower than that under high light. However, the quantum yield of trans-thylakoid pH gradient and xanthophyll-regulated thermal energy dissipation (YNPQ) was higher than that of high light. It indicated that responses of O.basilicum ‘purple ruffles’ and O.gratissimum seedlings to low light were different. The low light was beneficial to promote recovery in leaves of O.gratissimum seedlings after releasing low temperature stress, and low light led to O.basilicum ‘purple ruffles’ seedlings to extend recovery time from low temperature. The Fv/Fm in leaves of O.gratissimum seedlings was decreased under high light after low temperature, and photoinhibition in leaves of O. gratissimum seedlings was occurred. Photoinhibition in leaves of O.basilicum ‘purple ruffles’ seedlings was not occurred under high light because of the high content of anthocyanins in leaves, which played the role of the light attenuation and filtration. The high light decreased of YPSⅡ and increased quantum yield of thermal dissipation associated with the presence of non-functional PSⅡ (YNF) in leaves of O.gratissimum seedlings after low temperature, while high light resulted in the increase of YPSⅡ and the decrease of YNPQ in leaves of O.basilicum ‘purple ruffles’ seedlings after low temperature pretreatment. It concluded that anthocyanin in leaves of O.basilicum ‘purple ruffles’ played a role in plant photoprotective mechanisms.
A pot experiment was conducted to examine the effects of variable rates of nitrogen application (0, 30, 60 and 90 kg N·ha-1, hereafter referred as N0, N30, N60 and N90 respectively) on growth of alfalfa (Medicago sativa), plant N content and soil nitrate N and ammonium N levels. The result showed that the dry weight per plant increased with N application rate at all the 4 cuts while this effect was weakened at the later cuts. The total accumulated growth (TAG) of both above-and under-ground parts increased with N application rate. The TAG of N30, N60 and N90 was higher than control (N0) by 1.88%, 13.88% and 21.99%, respectively. No significant effect of N rate on plant tissue N level was detected. The soil nitrate N level decreased first and then increased to a stable level, while the soil ammonium N level increased first and then decreased to a stable level. In all treatments, both nitrate and ammonium N levels in the soil were significantly lower than the level before planting. There was a 56.6%, 53.2%, 32.7% and 47.6% decrease in nitrate N and 38.8%, 27.1%, 35.3% and 28.1% decrease in ammonium N for N0, N30, N60 and N90 respectively.
Effect of mowing(M), mowing + grazing(M+G), continuous grazing(CG) and rotational grazing(RG) on the nutrients of soils and herbages, and the botanical composition of mixed Lolium perenne+Trifolium repens pasture on Guizhou plateau were quantity monitored and analyzed, which would provide some practical basis for the grassland sustainable utilization. The results showed that, the contents of the nutrition in soil varied largely, the soil of CG grassland was severely acidification. For herbage, contents of Ca in M grassland, P in RG grassland, Cu in M and M+G grassland were higher than the other, and content of Mg in CG was lowest; while the nutritive values of four treatments had no significant difference. The number of tillers of L.perenne were RGM+GM=CG, and the tiller weight were M=M+GCG=RG; while the density and weight of T.repens stolon were M=RGM+G and CG. The number of species were CGM=M+GRG. The community structure of CG grassland was complex and dominated by Eragrostis pilosa, M grassland dominated by T.repens+Taraxacum officinale+Artemisia lactiflora; while the community structure of M+G and RG grassland were simple and dominated by L.perenne+T.repens. Thus, ultilization method of M+G and RG were more suitable for long term grassland utilization in research area.
Effects of 8 different planting models of Italian ryegrass and Smooth vetch on above ground biomass and quality were studied in Liangshan Prefecture. The results showed that, the hay yields of planting sowing treatments were significantly higher than that of single planting treatments(P0.05). Compared with treatments of single planting Italian ryegrass and Smooth vetch, the yields of interplanting treatments increased by 1.90%~8.45% and 38.16%~47.04%, respectively. The highest hay yield(17 730.53 kg·ha-1) and crud protein yields(2 520.13 kg·ha-1) were observed in treatment A6(50% Italian ryegrass+50% Smooth vetch). Under this planting model, land usage efficiency were improved by 55%. Besides, compared with single plant Italian ryegrass and Smooth vetch, its hey yield improved by 43.19% and 94.15, and crud protein improved by 90.59% and 71.18%, respectively. According to the analysis of grass yield, crud yield and land equivalent ratio, higher interspecific synergistic benefits were generated, and relative high hay yield were produced by applying the planting model of 50% Italian ryegrass+50% Smooth vetch in Liangshan Prefecture.
Medicago sativa is an important forage grass. It was widely cultivated internationally due to its good quality. A field experiment was carried out to compare the adaption of twelve alfalfa cultivars introduced from abroad during 2009 to 2011, by measuring their agronomic characters in Tianzhu County. The results showed that, four alfalfa varieties(Platini,Sanditi,Alfalfa King adn Alize)performed well in alpine pastoral area, and agronomic characters were obviously higher than other cultivars. It was suggested that these four alfalfa cultivars were suitable for establishing pastures in the alpine pastoral areas.
To provide foundation for researches on vegetation succession and mechanism of heterogeneity formation in alpine meadow, changes of vegetation composition, forage nutrients, plant importance value, plant niche breadth and plant niche overlap in Tibet Plateau alpine meadow with yak dung depositing were quantitative analyzed in this study. The results showed that, yak dung deposition significantly increased herbage biomass, green matter weight, plant height, coverage and K content of herbage, but had no significant influence on dead matter biomass and number of species. For dominant species, yak dung deposition decreased importance values of Stipa purpurea, Koeleria cristatav and Kobresia humilis, increased niche breadth values of these three species, and increased importance values of K.capillifolia and Agropyron cristatum. So yak dung deposition made these dominant species become to generalization species. For accompanying species, yak dung deposition decreased importance value of S.aliena, increased importance vale of S.krylovii, and decreased importance value and niche breadth value of Polygonum viviparum. For few species, yak dung deposition increased niche breadth values of Elymus nutans, Aremisia Smithii, A. capillaries, A. frigida, Allium sikkimense and Stellera chamaejasme. Beside, yak dung increased the whole niche overlap value of plants, increased species pairs, whose overlap values were 0.85, by increased 13.8%, while decreased species pairs, whose overlap values were0.45, by 42.9%. In a word, yak dung deposition increased the proportion of grasses, and promoted the meadow transformation from sedge+grasses community to grasses community or grasses+sedges community.
In the study, wild Arthraxon hispidus population distributed in purple soil hilly area of different slope was taken as a test material, indicators like reproductive ramets quantitative characteristics, biomass structure, reproductive investment rate and reproductive redistribution were measured and analyzed. The result showed that wild A.hispidus on the 50° cross-section can complete life cycle. When the slope was larger, the variation coefficient of inflorescence traits and seed setting rate was greater. The slope significantly affected the maximum, minimum and average value of root, stem, leaf, inflorescence biomass. When the slope was larger, more biomass distributed into root and less biomass into inflorescence. The habitat significantly affected reproductive investment rate and reproductive redistribution when the slope value was larger, the value of reproductive investment rate and reproductive redistribution was lower. The wild A.hispidus had a strong ability to adapt to arid and barren sectional habitat. Therefore, wild A.hispidus was an excellent lawn grasses resources in protecting solid soil slope, and should be exploited and utilized.
200-day-old Sophora flavescens seedlings were transplanted into fields from greenhouse at different densities, including 2.50×105, 1.25×105, 0.83×105 and 0.63×105 seedling·ha-1 in March 2009, in order to explore effect of seedling density on growth of the plant. The experiment was randomly arranged with 4 treatments and each with 3 replicates (plot was 24 m2). Plants were measured in each month from June to October 2009, after transplanted. In total, dry mater of leaves, stems and roots increased with the decreasing of seedhing density. However, plants performed different in different months, in which some significant differences (P0.05) were found in leaf number, leaf fresh and leaf dry weight from July to October, leaf area, height, stem fresh weight, stem dry weight, root diameter, root fresh weight and root dry weight from August to October, and root length in August,among different treatments. Root weight of the density treatment of ≤1.25×105 seedlings·ha-1(68.9 g) was significant higher than that of the density with 2.5×105 seedlings·ha-1(41.2 g) (P0.05). This study indicated that 1.25×105 seedlings·ha-1 was the optimal density for the transplantation of S.flavescens.
With the method of path analysis, study was made on the changes of climate and grass yield on alpine grassland of Xinghai County, located in Three-Rivers Source Region of Qinghai Province. In the past 14 years, annual grass yield increased significantly, and showed a significant positive correlation with the accumulated ≥0 ℃ temperatures and the precipitation in growing seasons. At heading-flowering stage, atmospheric temperature and precipitation had greater impacts on grass yield. At maturing-Withering stage, the accumulated ≥0 ℃ temperatures had some impacts on grass yield, at flowering-maturing stage, average wind speeds had negative impacts on grass yield. In the past 14 years, annual atmospheric temperatures and precipitation kept increasing significantly. At heading-flowering stage, atmospheric temperature and precipitation increased significantly, at maturing-Withering stage, the accumulated ≥0 ℃ temperature increased significantly, at flowering-maturing stage, average wind speeds decreased significantly. During late growing period of grasses, improving of heat and moisture conditions and lowering of wind speed were favorable for grass yield. When atmospheric temperature and precipitation continue increasing, evaporation of soil may weaken, and such conditions will make grass yield promoted.
Sweep sampling is the most common method used to the community structure research for grassland grasshopper, it is easy and cost-effective. To study the effects of sampling time on the community structure research for grassland grasshopper with sweep sampling, the collected data obtained from various times during 07:00-19:00 was compared in this study. The results showed that the caught numbers of adult and nymphal grasshoppers were not statistically different (P＞0.05) from 07:00 to 17:00. There were no significant differences (P＞0.05) in ratio of nymphs, community diversity, evenness and richness across times sampled. Regression analysis showed no correlation between grasshopper capture and temperature range from 18 to 28 ℃ (P＞0.05). In conclusion, the suitable time for grasshopper community research with sweep sampling is from 17:00 to 07:00 clock.
Yeast from the different samples such as the polluted water, soil and slightly rot fruit and so on was enriched, separated, purified and selected, and 4 yeast strains for tolerance to high temperatures, low acid and alcohol, named JM-1,JM-2,JM-3 and JM-4, were obtained. The results showed that the best suitable to five-carbon sugar concentration, alcohol, acidity and temperature of 4 yeast strains were 12 g·L-1, 14% (volume ratio), between 2.5 to 3.0 as well as 37 ℃ by morphological and physiological characterization respectively. The results indicated that strains JM-1, JM-2 and JM-4 belonged to the genus Meyerozyma, and strain JM-3 belonged Pichia using sequence analysis of 26S rDNA D1/D2 region. Selected yeast strains expressed good quality and performance on behalf of tolerance to high temperature, alcohol, low acid, and had some research significance.
Sophora alopecuroides and corn straw were mixed and silaged at radio of 10∶0, 8∶2, 6∶4, 4∶6, 2∶8 and 0∶10, respectively. The nutrition composition, fermentation quality and alkaloid content were measured after 30, 45 and 60 d ensilage, the aim of this study was to seek optimal mixed silage radio and ensiling days of S.alopecuroides and corn straw, improve the fermentation quality and nutrition composition, and reduce the content of alkaloid. The result showed that with the proportion of S.alopecuroides increasing, pH, ammonia/total nitrogen and crude protein would increase, while the lactic acid, neutral detergent fiber and acid detergent fiber has a descending trend, the alkaloid content of all mixed silage was significantly lower (P0.05) than raw material of S.alopecuroides. The mixed silage with S.alopecuroides and corn straw 2∶8 was best, the pH value was reduced to 3.95~4.01(4.2), the content of crude protein was 52.98%~64.69% higher than that of single corn straw silage, the alkaloid content was 65.63%~66.41% lower than raw material of S.alopecuroides. Ensiling days had no significant effect on the fermentation quality and content of alkaloid.
This study is to evaluate effects of adding previously fermented juice and cellulose enzyme on the fermentation quality of King grass silages. The experimental treatments were CK(no additive), PFJ(previously fermented juice), CEL(cellulose enzyme)and PC(previosly fermented juice and cellulose enzyme). Silos were opened after seven ensiling periods(1, 2, 3, 5, 7, 14 and 30 days of ensiling)and the fermentation qualities(pH value, VFAS, the contents of ammonia-N and WSC and other chemical composition)were analyzed. All treatments did not influence the DM after ensiling. There was well reflected faster and larger pH decline and lactic acid production during the first day of ensiling and the lowest pH value in the 5th day of ensiling. All additive treatments had a significantly(P0.05)lower pH value than CK. Lactic acid, acetic acid, propionic acid, total volatile fatty acid content and AN/TN value rose gradually, and the change of butyric were contrary in between PFJ and CK. Propionic acid and butyric acid were not found in PC, PC also hold concurrently the advantage of PFJ improved crude protein content and CEL reduced neutral detergent fiber content to increase water soluble carbohydrate content. These results showed that mixing add previosly fermented juice and cellulose enzyme to the silage was the optimum for fermentation quality of King grass.
In order to study the adsorption of Cr6+ with garlic bolt slag, garlic slag was used as adsorption materials, and effects of five factors were analyzed such as adsorption rate of Cr6+ concentration, garlic bolt slag quantity, the solution to pH value, adsorption temperature and adsorption time. The five factors were studied using two regressions orthogonal rotating combination designs. From the model, it could be concluded that the best adsorption rate was 94.14% when pH was 5, temperature was 40 ℃, time was 2 h, concentration was 40 mg·L-1, addition amount was 0.5 g. From the experiment, it could be concluded that garlic bolt slag could be used for adsorbing low concentration wastewater. The isothermal adsorption Langmuir and Freundlich model could describe isothermal adsorption behavior of Cr6+ in garlic bolt, Langmuir model was fit than Freundlich. From the dynamics experiment of garlic bolt absorption Cr6+, conclusion was made that the adsorption processes fitted the secondary dynamic model. It indicated that adsorption process was a mixed adsorption process and chemical adsorption was given priority to physical adsorption. Secondary dynamic adsorption curve could well describe the adsorption dynamics condition.
Grassland ecosystems provide human with ecological functions and services. However, due to dual impact from human activities and natural factors, the ecological and economic problems triggered by grassland degradation are becoming increasingly prominent. Evaluating the grassland ecosystem services is significantly meaningful for grassland protection and decision-making in economics. The ecosystem services of Xin Barag Youqi grassland were firstly evaluated using multiple eco-economics methods. The result showed that the total value of the ecosystem services of Xin Barag Youqi grassland was about 200.69×108 CNY·a-1, among which, the value of hay production equaled 7.89×108 CNY·a-1, atmosphere regulation 4.207×109 CNY·a-1, water source conservation 1.78×109 CNY·a-1, soil conservation 1.287 9×1010 CNY·a-1, nutrient cycling 2.51×108 CNY·a-1, waste degradation 9×106 CNY·a-1, recreation and culture 1.54×108 CNY·a-1. Functional value of ecosystem services is soil conservationatmosphere regulationwater source conservationhay productionnutrient cyclingrecreation and culturewaste degradation.
The healthy and production level of natural pasture, which is one of the most important utilization terminals of grassland, depend on its management level. With the developing of information technologies, and the quantifying and segmenting of ecological studies, studies on pasture management model and how to use these models to guide actual production have become one of the hotspots of modern grassland agricultural study. As one of grazing system models, pasture management model is the decision support system(DSS) of grassland production and livestock production. It simulates the effects of different production and management modes, and guides actual production, by collecting data of grassland growth, livestock growth, livestock production and management modes. To provide references for domestic researches on pasture management model, research advances on pasture management model at home and abroad were reviewed, and further prospect on development of pasture management model in future was made in this study.
At present, alfalfa industry is booming in China, many risks existed in alfalfa industry has not attracted much attention. Regarding the risk, 36 kinds of risk characteristics, possible hazards and prevention ways were studied through climate, soil, biological, technical, management and market, including 6 meteorological risks, 10 soil risks, 5 kinds of biological risks, 5 technology risks, 6 management risks and 4 market risks. It also pointed out that the risk consciousness should be enhanced, the mechanism of risk management should be established and risk prevention and control system to enhance the ability of risk prevention in alfalfa industry should be set up.