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1.
通过研究高油玉米秸秆青贮发酵过程中营养成分和发酵参数变化的动态(试验1),以及青贮浸提液对活体外瘤胃发酵的影响(试验2),初步探明导致高油玉米秸秆青贮提高瘤胃发酵程度的因素。试验1结果显示发酵1周内,可溶性糖损失50%以上,pH降到4.0以下;乳酸含量在6周内逐步升高,而后保持不变,其他营养成分保持稳定;试验2结果表明,添加青贮浸提液后与对照组相比,最大产气量显著增加(P<0.000 1),产气速度加快(P<0.000 1),产气延滞期缩短(P=0.000 8)。其中青贮浸提液灭菌处理与否不影响产气动态参数。添加2种青贮浸提液会导致活体外人工瘤胃发酵pH显著降低(P<0.000 1)。对照组活体外瘤胃发酵液中乙酸摩尔分数最低(67.79%),其次为添加未处理浸提液组(78.48%)和灭菌浸提液组(80.19%),并且3个处理组差异显著(P<0.000 1)。丙酸摩尔分数也差异显著(P<0.000 1),其中对照的丙酸摩尔分数最高,达到21.76%,而其他2个处理组分别为8.81%和6.84%。对照组中异丁酸和异戊酸的摩尔分数均最高,分别为0.66%和0.85%。结果表明,高油玉米秸秆青贮在1周内发酵过程变化很大,发酵6周后,进入稳定阶段。添加青贮浸提液影响活体外瘤胃发酵模式,高油玉米秸秆青贮浸提液的营养成分可能是影响瘤胃微生物发酵的主要因素。  相似文献   

2.
添加酶制剂对青贮玉米秸发酵品质和化学成分的影响   总被引:4,自引:0,他引:4  
以新鲜玉米秸为原料,分别添加酶制剂Cornzyme0,500,750,1000mL/tDM进行青贮.感观评定得知各处理青贮料均属于优质青贮料.Cornzyme的添加降低了青贮玉米秸的中性洗涤纤维和酸性洗涤纤维含量,其中以添加1000mL/t组降低最多,分别比未添加组(对照组)降低7.0%和4.8%.青贮料的乳酸含量分别为132.9,122.5,129.9,146.7g/kgDM,添加1000mL/t组使乳酸含量较对照组提高了10.4%;青贮料的乙酸含量随Cornzyme添加水平的提高而增加(分别为15.5,17.3,18.6,24.2g/kg),比对照提高11.6%,19.4%和56.1%;青贮料总有机酸含量分别为149.5,140.8,149.6,170.9g/kg,添加1000mL/t组比对照高14.3%.试验组和对照的青贮料均不含丁酸.添加Cornzyme对青贮玉米秸的干物质、粗蛋白和可溶性碳水化合物的含量以及对pH值、氨态氮占总氮之比值均无显著影响.青贮玉米秸的干物质回收率以试验组为低(分别为94.0%,88.2%,88.8%,87.1%).  相似文献   

3.
An in vitro rumen gas production technique was employed to determine the methane production and fermentation characteristics of Leymus chinensis and Medicago ruthenica at differing harvest dates(May 15,May 30,June 30,July 30,August 30 and September 30),which are sequential phases within a single continuous growth of two 10-year-old pastures.To quantify the rate of degradation and compare in vitro rumen fermentation characteristic,a logistic-exponential model,where initial gas volume was zero(LE_0),was used to fit gas production and methane output results.Dried,milled forage samples were incubated in vitro for 72 h at 39℃ and gas production was recorded intermittently throughout the incubation and gas samples were collected to measure methane production.Results showed that there were significant interactions between species and harvest for all chemical composition variables(P0.001) and condensed tannin content(P0.001).L.chinensis produced more total gas and methane than M.ruthenica(P0.001).Both total gas and methane production decreased lineally(P0.001) with advancing harvest date.The degradation rates of L.chinensis and M.ruthenica harvested on September 30 were lower than those on the other harvest dates(P0.01).M.ruthenica fermented fluid had higher concentration of ammonia N(P0.05) and molar proportions of isobutyrate(P0.01),valerate(P0.001) and isovalerate(P0.01) in total volatile fatty acids than L chinensis.Furthermore,concentration of isovalerate decreased cubically with advancing harvest date(P0.05).In conclusion,M.ruthenica produced less methane than L.chinensis and the total gas and methane production decreased with advancing harvest date for both species,which may be due to the changes in contents of chemical compositions and condensed tannin in forages.  相似文献   

4.
Planting under plastic-film mulches is widely used in spring maize production in arid-cold regions for water conservation and warming the soil.To ameliorate the associated issues such as plastic-film residues and additional labor during the“seedling release” in spring maize production, we have developed a plastic-film-side seeding (PSS) technology with the supporting machinery.In the semi-arid regions of Northwest China, a 7-year trial demonstrated that PSS increased plant number per hectare by ...  相似文献   

5.
The objective of this study was to observe the forage yield, silage fermentative quality, anthocyanin stability, and antioxidant activity during the storage period and in vitro rumen fermentation of anthocyanin-rich purple corn (Zea mays L.) stover (PS) and sticky corn stover (SS). Forage yield of corn stover was weighed and ensiled with two treatments: (1) hybrid sticky waxy corn stover (control), and (2) hybrid purple waxy corn stover (treatment). Samples were stored in mini-silos for periods of 0, 7, 14, 21, 42, 63, 84, and 105 d. The results showed that PS had significantly higher (P<0.05) yields of dry matter (DM), organic matter (OM), gross energy (GE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and total anthocyanins than that of the SS. Anthocyanin-rich purple corn stover silage (PSS) showed higher (P<0.05) levels of DM and CP relative to the sticky corn stover silage (SSS). Although anthocyanin-rich PSS displayed a lower (P<0.05) level of pelargonidin-3-glucoside (P3G), it had higher (P<0.05) levels of peonidin (Peo) and pelargonidin (Pel) compared to the control. Delphinidin (Del) and malvidin (Mal) were not detected in SSS during the ensilage period; in PSS, Del was no longer detected after 7 d of ensilage. Specifically, total anthocyanins in anthocyanin-rich PSS decreased rapidly (P<0.05) prior to 7 d of ensilage, and then remained at relatively stable (P>0.05) constants. Compared to the anthocyanin-rich PSS, SSS displayed significantly higher (P<0.05) pH value and ammonia nitrogen (NH3-N) content. Propionic acid (PA) at 0 d and butyric acid (BA) during the entire study period were not detected, whereas anthocyanin-rich PSS showed a higher (P<0.05) level of lactic acid (LA) than that of the SSS. Compared with the SSS extract, anthocyanin-rich PSS extract showed a higher (P<0.05) level of 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and displayed a lower (P<0.05) half maximal inhibitory concentration (IC50) value. Moreover, anthocyanin-rich PSS reduced (P<0.05) gas production (GP), and displayed lower levels of immediately soluble fraction and ratio of acetic acid (AA) to PA at 12 h, but the other parameters were unaffected (P>0.05) relative to the control. Taken together, the results indicated that: (1) anthocyanins could be stable in silage; (2) anthocyanin-rich PSS showed better silage fermentative quality and stronger antioxidant activity; and (3) anthocyanin-rich PSS had no negative effect on rumen fermentation parameters.  相似文献   

6.
This experiment was conducted to study the effect of molasses on the fermentation characteristics of mixed silage ensiled rice straw and vegetable by-products with alfalfa.Mixture(202 g kg~(–1) dry matter(DM))consisting of rice straw,broccoli residue and alfalfa at the ratio of 5:4:1 was ensiled with three experimental treatments:(1)no additives(control);(2)molasses at 2.5%(M1);(3)molasses at 5%(M2)on a fresh matter basis of mixture,respectively.All treatments were packed into laboratory-scale silos,and three silos per treatment were sampled on days 1,3,5,14 and 30.The result showed that the p H value of all mixed silages decreased gradually with the time of ensiling except for the control silage,in which a significant increase(P0.05)on day 30 occurred.The lactic acid content increased gradually with the time of ensiling and reached the highest value on day 14,and a marked decrease(P0.05)was found in the control silage on day 30.The changes of acetic acid content showed similar pattern with lactic acid content.A trace amount of propionic and butyric acid contents were found in the three mixed silages during the fermentation period.Comparing to the control,M1 and M2 treatments improved the fermentation quality of mixed silages as indicated by higher(P0.05)lactic acid contents and lower(P0.05)p H and ammonia-N contents.The Flieg points also showed that M1 and M2 silages were well preserved,whereas the control silage had a bad quality.Overall,the findings of this study suggested that adding molasses could improve fermentation quality of mixed silage,and M1 was more suitable for practical application.  相似文献   

7.
我国北方早熟玉米区高密度、超高密度栽培的品种选择   总被引:1,自引:0,他引:1  
试验表明,品种间的耐密压力能力差异明显,元华1号、哲单37、FC-254具有较高的耐密能力。品种的适宜密度,龙单13(ck1)为4.9千株/亩,元华2号、FC-254、哲单37(ck2)、元华1号分别为5.0、5.6、6.3、6.5千株/亩。各品种最高产量密度处理的产量差异明显,元华2号(DM2)、FC-254(FM3)较ck1龙单13(AM1)、ck2哲单37(BM3)增产达极显著、显著水平,元华1号较两对照有较大增幅,未达显著水平。随密度增加株粒重下降程度所表达的耐密压力能力与上述结果亦有高度的吻合性。随密度的增加,穗粒体积的下降主要体现在穗长的下降,其次为穗径、轴径的下降。穗粒重的下降主要体现在穗粒数的下降,其次是百粒重的下降。穗粒数的下降主要体现在行粒数的下降,其次为穗行数的下降。  相似文献   

8.
Now,lodging is a major constraint factor contributing to yield loss of maize (Zea mays L.) under high planting density.Chemical regulation and nitrogen fertilizer could effectively coordinate the relationship between stem lodging and maize yield,which significantly reduce lodging and improve the grain yield.The purpose of this study was to explore the effects of chemical regulation and different nitrogen application rates on lodging characteristics,grain filling and yield of maize under high density.For this,we established a field study during 2017 and 2018 growing seasons,with three nitrogen levels of N100 (100 kg ha~(–1)),N200 (200 kg ha~(–1)) and N300 (300 kg ha~(–1)) at high planting density (90 000 plants ha~(–1)),and applied plant growth regulator (Yuhuangjin,the mixture of 3% DTA-6 and 27% ethephon) at the 7th leaf.The results showed that chemical control increased the activities of phenylalanine ammonia-lyase (PAL),tyrosine ammonia-lyase (TAL),4-coumarate:Co A ligase (4CL),and cinnamyl alcohol dehydrogenase (CAD),and increased the lignin,cellulose and hemicellulose contents at the bottom of the 3rd internode,which significantly reduced the lodging percentage.The lignin-related enzyme activities,lignin,cellulose and hemicellulose contents decreased with the increase of nitrogen fertilizer,which significantly increased the lodging percentage.The 200 kg ha~(–1) nitrogen application and chemical control increased the number,diameter,angle,volume,and dry weight of brace roots.The 200 kg ha~(–1) nitrogen application and chemical control significantly increased the activities of ADP-glucose pyrophosphorylase (AGPase),soluble starch synthase (SSS) and starch branching enzyme(SBE),which promoted the starch accumulation in grains.Additional,improved the maximum grain filling rate (V_(max)) and mean grain filling rate (V_m),which promoted the grain filling process,significantly increased grain weight and grain number per ear,thus increased the final yield.  相似文献   

9.
The objective of this study was to investigate the effect of lactic acid bacteria(LAB) inoculums on fermentation quality and in vitro digestibility of corn stover silage. Corn stover was ensiled without(control) or with Lactobacillus plantarum(LP), Enterococcus faecalis(EF), and Enterococcus mundtii(EM) for 45 days. The fermentation characteristics were assessed, and subsequent in vitro dry matter digestibility(DM-D), neutral detergent fiber digestibility(NDF-D), volatile fatty acids(VFA), methane(CH_4) production, cellulolytic bacteria proportions and their activities per corn stover silage were also determined. There was no significant difference(P0.05) among the silage pH, lactic acid, crude protein(CP), water soluble carbohydrates(WSC) and lignocelluloses contents of different treatments. The relative proportions of Ruminococcus flavefaciens and Fibrobacter succinogenes, carboxymethyl-ocellulose and β-glycosidase activities, DM-D, NDF-D, and VFA production of in vitro incubation was higher(P0.05) for silages inoculated with LP and EF than those of the control silage. Silage inoculated with LP showed the lowest(P0.05) CH_4 production per unit yield of VFA, which was positively corresponded to the lowest(P0.05) ratio of acetate to propionate. In summary, the ensiling fermentation quality and subsequent utilization of corn stover silage were efficiently improved by inoculated with L. plantarum.  相似文献   

10.
近年来黄淮海平原夏玉米区花期高温频发,常引起玉米花粒现象,严重影响夏玉米籽粒产量和品质。花期高温已成为影响该地区玉米丰产稳产的主要限制因素之一。基于当前研究现状,综述近年来黄淮海地区玉米季气候变化规律及高温热害发生特点;基于源库理论与产量形成特点,进一步分析玉米花期高温危害特点及其影响机理。还从品种选择、种植方式、耕作方式与水肥管理等方面综述当前高温热害的栽培技术防控措施。玉米花期高温发生常伴有干旱特点,加大了危害程度与危害机理研究难度,从而影响对玉米花期高温的有效防控。因此花期高温与干旱叠加危害机理及其防控措施研究将是未来黄淮海地区玉米丰产、稳产的研究重点。  相似文献   

11.
广西蔗糖业发展特点与加入WTO的应对措施   总被引:2,自引:0,他引:2  
农业是我国加入 WTO后受影响较大的领域之一。蔗糖业如何扬长避短、趋利避害 ,采取有效措施保护和发展 ,确保其优势地位 ,提高其国际竞争力 ,是我区面临的新课题。  相似文献   

12.
Increasing the planting density is one way to enhance grain production in maize.However,high planting density brings about growth and developmental defects such as barrenness,which is the major factor limiting grain yield.In this study,the barrenness was characterized in an association panel comprising 280 inbred lines under normal (67 500 plants ha–1,ND) and high (120 000 plants ha–1,HD) planting densities in 2017 and 2018.The population was genotyped using 776 254single n...  相似文献   

13.
淮河流域氮肥农药施用的合理性及其环境影响   总被引:3,自引:3,他引:3  
根据1990-2008年统计数据和相关参数,通过估算农田系统氮素平衡和农药施用水平来分析淮河流域中下游典型区氮肥农药施用的合理性及其对环境的影响.结果表明,淮河流域研究区N素盈余量和农药施用量呈增加趋势,1990-2008年按耕地平均,N素盈余量由227 kg·hm-2增加到453 kg·hm-2,农药使用量从7.43kg·hm-2增加到22.63kg·bm-2.从空间差异来看,在研究区的8个县中,6个县耕地N素盈余量在400 kg·hm-2以上,2个县耕地氮素盈余量超过600kg·hm-2;5个县农药使用量在20.00kg·hm-2以上,2个县农药使用量超过30.00kg·hm-2.8个县中N素盈余量和农药施用量最高的分别是最低的2.54倍和5.29倍.综合潜在风险分级结果为:沈丘、淮滨、凤台、寿县属于高风险区,五河、霍邱、颍上属于中等风险区,临泉属于较低风险区.可见,该地区氮肥和农药施用量大,且分布不平衡.  相似文献   

14.
The combined use of chemical and organic fertilizers is considered a good method to sustain high crop yield and enhance soil organic carbon(SOC),but it is still unclear when and to what extent chemical fertilizers could be replaced by organic fertilizers.We selected a long-term soil fertility experiment in Gongzhuling,Northeast China Plain to examine the temporal dynamics of crop yield and SOC in response to chemical nitrogen,phosphorus,and potassium(NPK) fertilizers and manure,applied both individually and in combination,over the course of three decades(1980-2010).We aimed to test 1) which fertilizer application is the best for increasing both maize yield and SOC in this region,and 2) whether chemical fertilizers can be replaced by manure to maintain high maize yield and enhance SOC,and if so,when this replacement should be implemented.We observed that NPK fertilizers induced a considerable increase in maize yield in the first 12 years after the initiation of the experiment,but manure addition did not.In the following years,the addition of both NPK fertilizers and manure led to an increase in maize yield.SOC increased considerably in treatments with manure but remained the same or even declined with NPK treatments.The increase in maize yield induced by NPK fertilizers alone declined greatly with increasing SOC,whereas the combination of NPK and manure resulted in high maize yield and a remarkable improvement in SOC stock.Based on these results we suggested that NPK fertilizers could be at least partially replaced by manure to sustain high maize yield after SOC stock has reached 41.96 Mg C ha~(-1) in the Northeast China Plain and highly recommend the combined application of chemical fertilizers and manure(i.e.,60 Mg ha~(-1)).  相似文献   

15.
为明确推迟收获对华北地区夏玉米籽粒脱水及其力学特性的影响,筛选适宜该区域的机械收获籽粒品种,选取28个在该地区大面积推广的品种,综合分析籽粒含水率、穗/粒剪切力和产量变化。结果表明,推迟收获日期,平均籽粒含水率从35.5%下降至27.4%,而籽粒抗破损能力则显著上升(P0.01)。籽粒含水率与静压破损峰值呈极显著负相关,其中影响最大的是顶部剪切力(R=-0.796)。产量与含水率和力学特性之间没有显著相关性。因此,结合产量选择低含水率,高抗破损能力的品种是可行的。10月2日正常收获,‘京农科728’同时满足10 t/hm~2高产且籽粒机械收获最低含水率28%的要求。收获推迟10 d,则‘豫单112’和‘登海701’可以作为该区域玉米籽粒机械收获的备选品种。  相似文献   

16.
在北农大高油(BHO)玉米群体的16个选择轮次中隔轮选取籽粒样品为试验材料,利用活体外人工瘤胃产气量方法,研究HOC籽粒含油量的选择进程对BHO群体籽粒的化学组成、活体外干物质和淀粉消化率以及瘤胃发酵参数的影响。BHO群体的籽粒含油量从第2轮的6.84%提高至第16轮的13.20%,分别与籽粒淀粉和蛋白质含量呈现显著的负相关(r=-0.84,P<0.001)和正相关(r=0.74,P<0.001)。随着含油量选择进程的提高,HOC籽粒的活体外产气速度和淀粉消化率线性增加(P<0.001),这可能源于BHO群体的淀粉结构随含油量选择进程发生了改变。理论最大产气量和活体外干物质消化率随含油量选择轮次的提高而线性降低(P<0.001)。活体外发酵6 h的pH、总挥发酸(mmol/L)和丙酸比例(%)线性提高(P<0.001),乙酸和丁酸的比例线性下降(P<0.001)。活体外发酵24 h以后,不同选择轮次间的各项发酵参数均无显著差异。  相似文献   

17.
农林复合系统作为一种传统而又新兴的土地利用和经营方式在改善商洛生态环境、增加该区农民收入、促进其生态和经济协调发展等方面发挥着非常重要的作用.为了研究林下作物的生理生态特性,对研究区农林复合系统中不同处理大豆、丹参的光合、叶绿素荧光参数进行了系统观测.结果表明,从单作到距核桃1m处,距核桃树越近,遮光愈多.各处理大豆的光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)表现出与光合有效辐射(PAR)基本一致的日变化趋势.不同处理丹参光合速率日变化趋势各不相同,且出现“午休”现象.与单作相比,各处理大豆、丹参的光合速率、气孔导度和蒸腾速率均有不同程度的降低.随着遮荫程度的提高,大豆、丹参叶绿素含量和表观量子效率(Φ)升高,光饱和点(LSP)和光补偿点(LCP)降低.二者叶绿素荧光参数最大光能转换效率(Fv/Fm)、PSⅡ电子传递量子效率(ΦPsⅡ)以及光化学猝灭系数(qP)均有不同程度的升高,而非光化学猝灭系数(qNP)却逐渐降低.说明大豆、丹参能适应弱光环境,在较低的光照条件下正常生长.  相似文献   

18.
This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration(TMR) silage. Total mixed ration was ensiled with four treatments:(1) no additives(control);(2) an inoculant(Lactobacillus plantarum)(L);(3) propionic acid(P);(4) propionic acid+lactic acid bacteria(PL). All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for 12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH(3.80) and ammonia nitrogen(NH_3-N) contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH_3-N contents of TMR silage compared to the control(P0.05). After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly(P0.05) increased them. L silage had higher(P0.05) in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage.  相似文献   

19.
基于畜禽生产-污染防治大协同、污水-废气-固废处理小协同目标,开展各畜禽养殖模式氨排放特征分析。研究发现:相同清粪方式下,机械通风封闭化圈舍氨排放速率要小于自然通风开放式圈舍,相同通风方式下,圈舍氨排放速率表现为水冲粪 < 干清粪 < 垫草垫料 < 水泡粪,各畜种肥水储存模式氨排放最大;通过养殖模式与减排技术的政策、规范协调性分析,发现圈舍封闭化+机械通风、堆肥发酵、厌氧发酵等养殖模式,低蛋白日粮、排风口处理、覆盖、密闭堆肥+废气处理、粪肥机械深施等控氨技术可作为畜牧业氨减排的方向。明确了氨减排模式与技术的对应关系,构建了模式替代和技术减排相耦合的畜禽氨减排体系,提出了制定大气氨环境质量标准、畜禽养殖氨排放标准及配套的氨监测技术规范、畜禽养殖场氨减排核算技术规范及配套的氨减排工程建设技术规范等配套落地政策建议,为顺利推动畜禽氨减排试点工作提供技术支撑。  相似文献   

20.
通过文献整理,并结合杭州市实际,对我国城市生活垃圾的特点及其综合处理技术进行探讨。结果显示,与发达国家相比,我国城市生活垃圾中厨余垃圾占比过高,可回收物含量高。因此,十分有必要从源头开展垃圾分类,针对不同垃圾的特性,分类处理。同时,由于我国城市生活垃圾中厨余垃圾占比超过50%,因而在城市生活垃圾的综合处理中,应重点关注厨余垃圾的处理。目前,主要的厨余垃圾处理方式有饲料化、填埋沼气利用、生物堆肥及厌氧发酵处理等,但总体来看,这些技术还不够成熟,仍有待进一步研究。最后,结合杭州市实际,针对城市生活垃圾的综合处理,提出加快推进垃圾分类、强化垃圾处理技术攻关、加强政策保障的建议。  相似文献   

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