基于知识图谱的我国青贮玉米研究领域可视化分析

以1992～2019年中国知网(CNKI)数据库收录的721篇青贮玉米研究的核心期刊论文为研究对象,运用文献分析法,并借助CiteSpace软件绘制知识图谱,对我国青贮玉米研究的文献分布、刊物分布、研究机构、研究热点与趋势等进行可视化分析,全面把握我国青贮玉米领域研究的发展进程,为我国青贮玉米理论研究提供有价值的参考....     

不同添加剂对柱花草青贮品质的影响

以热研2号柱花草为原料， 通过直接青贮（CK）、 添加山梨酸（0.2％）、 蔗糖（2％）、 青贮宝（0.1％）等处理， 30 d后测定了柱花草青贮饲料pH值、 乳酸、 乙酸、 丙酸、丁酸等含量并分析其主要营养成分含量。结果表明： 柱花草直接青贮品质较差， 添加山梨酸、 蔗糖、 青贮宝等处理能降低pH值和提高乳酸含量， 添加2％蔗糖能极显著降低pH值(p<0.01)、 提高乳酸含量(p<0.05)， 改善青贮品质， 提高营养价值。     

不同收获期玉米青贮DM和CP奶牛瘤胃降解率研究

结果表明：蜡熟期玉米青贮DM的有效降解率（60.07%）分别比乳熟期（52.91%）和乳熟前期（45.13%）高7.16个百分点（P＜0.05）和14.94个百分点（P＜0.01）;乳熟期玉米青贮DM的有效降解率比乳熟前期高7.78个百分点（P＜0.05）.蜡熟期玉米青贮CP的有效降解率（81.93%）分别比乳熟期（76.43%）和乳熟前期（73.36%）高5.50个百分点（P＜0.05）和8.57个百分点（P＜0.05）;乳熟期玉米青贮CP的有效降解率比乳熟前期高3.07个百分点，但差异不显著.     

Voluntary intake of silages in dairy cows depending on chemical composition and in vitro gas production characteristics

A study was conducted to investigate the possibilities to develop models for predicting the relative silage dry matter intake (SDMI) in dairy cows utilising information on chemical composition and in vitro gas production (GP) kinetics of silages. In five experiments, each with an average of 38 lactating dairy cows, SDMI was recorded for 15 grass silages made from primary growth and regrowth swards of timothy (Phleum pratense L.). The silages were characterised by chemical analysis and by utilising an automated in vitro GP recording technique with end point measurements of substrate residues. The silage samples were analysed both as dried and wet samples to evaluate the effects of sample preparation techniques on GP kinetics and their relations to SDMI. Relationships between feed variables and SDMI were investigated utilising simple linear and multiple regression. The wet silage samples had higher cumulative GP and different GP curves compared to the dried samples. The linear relationships between, GP variables, harvest number (first or second cut) of the grass, chemical characteristics of the silages and the relative SDMI show that the GP technique is a powerful tool to detect silage quality. By using the parameters from the dried samples the multiple regression analysis resulted in a relationship, relative SDMI (kg per 100 kg live weight (LW)) per day = 0.071 + 0.0029 × NDFD − 0.266 × C (R² = 0.82, S.D. = 0.06). NDFD is the degradability of the neutral detergent fibre (NDF) (g/kg NDF) and C is the variable that regulates the switching characteristics of the GP profiles. By using the wet silage samples the multiple relationship did not include any GP variable; relative SDMI (kg per 100 kg LW per day) = 1.86 − 0.008 × acetic acid (g/kg DM) + 0.024 × ethanol (g/kg DM) (R² = 0.62, S.D. = 0.08). The results from the regression analysis and the experience of the laborious sample preparation technique for wet samples, give the conclusion that dried silage samples are recommended for determining feed characteristics using the GP technique in intake studies.     

添加麸皮与纤维素酶对笋壳青贮后氰甙含量的影响

[目的]研究添加麸皮与纤维素酶对笋壳青贮后氰甙含量的影响。[方法]采用异烟酸—吡唑啉酮比色法研究添加麸皮与纤维素酶对笋壳青贮后氰甙含量的影响。[结果]添加麸皮与纤维素酶均可降低笋壳青贮后的氰甙含量。麸皮添加水平越高,青贮笋壳毒性越低,当麸皮添加水平为15%时笋壳青贮后氰甙含量最低。[结论]该研究可为笋壳饲料的资源化利用提供理论依据。     

青贮玉米育种和栽培的研究与探讨

主要对青贮玉米育种、栽培进行了浅析，并指出其发展前景，旨在推动我国青贮玉米育种研究再上一个新台阶。     

不同添加剂对晴隆白刺花青贮品质和营养价值的影响

试验通过添加不同种类的青贮剂研究其对晴隆白刺花青贮品质和营养价值的影响.试验设直接青贮、添加乳酸菌（1％FM）、纤维素酶（0.1％FM）、乳酸菌＋纤维素酶（1％ FM ＋0.1％ FM）、甲酸（6 mL/kg FM）、蔗糖（3％FM）及乳酸菌（1％FM）＋纤维素酶（0.1％FM）＋乳酸菌（1％FM）＋纤维素酶（0.1％FM）＋甲酸（6 mL/kg FM）＋蔗糖（3％ FM）7个处理.试验结果表明：青贮过程中pH值总体呈下降趋势,添加剂处理显著低于直接青贮,其中蔗糖的效果最为明显（pH值3.97）,乳酸菌＋纤维素酶＋甲酸＋蔗糖处理也低（pH值4.04）,品质较好;直接青贮的pH值相对较高（4.73）;青贮后晴隆白刺花的粗蛋白（CP）略有下降,乳酸菌＋纤维素酶＋甲酸＋蔗糖降幅最大,达11.18％,但CP含量仍较高,为15.41％,其他各处理CP均有所上升;单独青贮,晴隆白刺花的酸性洗涤纤维（ADF）虽略有增加,但粗纤维（CF）和中性洗涤纤维（NDF）均下降,且NDF降幅较大,达20.15％,而粗脂肪（EE）、无氮浸出物（NFE）含量相对增加,改善了晴隆白刺花的营养;各处理单宁含量均有所下降,其中甲酸处理的降幅最大,达47.83％,乳酸菌＋纤维素酶处理降幅相对较小.     

青贮玉米新品种引种试验初报

为筛选适宜临夏地区种植的优质高产青贮玉米品种,促进旱作生态区青贮玉米产业发展,在临夏县川塬灌区覆膜栽培条件下,对引进的13个青贮玉米新品种进行试验观察。结果表明,生物产量高于对照品种豫玉22号的品种共8个,其中铁研53、京九青贮16、大京九26较高,分别为123 297.8、121 464.4、119 172.6 kg/hm2,较对照品种豫玉22号分别增产14.47%、12.77%、10.64%;屯玉168、陇青贮1号、瑞青贮616、金穗1915、大唐8号分别为118 714.3、117 339.2、114 130.7、110 005.5、108 638.8 kg/hm2,较对照品种豫玉22号分别增产10.21%、8.94%、5.96%、2.13%、0.86%。依据青贮玉米品质分级标准,佳玉1017达到一级;屯玉168、陇青贮1号、金穗1915、京科627、登海3721、瑞青贮616达到二级。综合产量和品质因素,屯玉168、陇青贮1号、金穗1915、京九青贮16、大京九26、瑞青贮616适宜在临夏地区推广种植,铁研53作为高生物产量、佳玉1017作为高饲用品质推荐品种。     

施氮量与密度对西南地区主栽青贮玉米品种产量和品质的影响

以试验前期筛选适合西南地区高产优质青贮玉米品种为研究对象,采用再裂区试验设计,分别在两年三地进行试验,探究氮肥、密度、环境及其互作对青贮干物质产量、品质的影响。2018年结果表明,减氮施肥能替代传统施肥,干物质产量随施氮量的减少先增加后降低,随密度的增加逐渐升高。2019年在雅安和合川试点,减氮10%和 30%与常规施氮(纯氮 300 kg/hm²)相比,各品种干物质产量随密度增加先升高后降低,在密度 82 500株/hm²时产量最高;在怀化试点,减氮 10%处理下的干物质产量显著高于常规施氮和减氮 30%处理,干物质产量随密度增加而增加。氮密互作对青贮玉米品质影响不明显。综合分析两年干物质产量及品质,在种植密度 71 250～82500株/hm²搭配减氮 10%～30%时,青贮玉米产量达到最高且品质没有降低或降低不显著。     

Carbon sequestration in soils with annual inputs of maize biomass and maize-derived animal manure: Evidence from C abundance

The abundance of ¹³C was determined over a period of nine years in two soils (LUN, coarse sand; ASK, sandy loam) following their conversion from C3-crops and to the C4-crop silage maize (Zea mays L.). The soils were exposed to identical management and climatic conditions, and were sampled every second year. The aboveground maize biomass was either removed (stubbles and roots left), chopped and added to the soil, or fed to sheep and the faeces then added to the soil. Annual inputs of maize biomass and sheep faeces were similar (0.8 kg DM m⁻²). The study included soils maintained under C3-crops (beet roots, Beta vulgaris L.). After nine years of maize cropping, soil C from stubbles and roots accounted for 12 and 16% of the total-C in the LUN and ASK soil, respectively. Without additional organic amendment the content of total-C in the ASK soil remained constant and similar to that of soil retained under C3-crops whereas total-C tended to decrease in the LUN soil. When maize biomass and sheep faeces were added, soil total-C increased and C from these C4-sources averaged 14% and 21% of the soil total-C, respectively. Following nine annual additions, retention of C added in aboveground maize biomass averaged 19% while the retention of C added in maize-derived faeces was 30%. Our study infers that that ruminant manure C contributes about 50% more to soil C sequestration than C applied in crop residues.