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1.
粮饲通用型玉米产量高品质优良,在生产上应用越来越广泛。为探讨其适宜种植密度,以4个粮饲通用型玉米品种登海605、登海圣丰168、青农118和天泰366为试验材料,研究4个种植密度(4.5×104、6.75×104、9×104和11.25×104株/hm2)对粮饲通用玉米产量和饲用品质的影响。结果表明,在一定范围内随着种植密度的增加,玉米的鲜草和干草产量呈增加的趋势。种植密度对中洗涤纤维影响不显著,对酸性洗涤纤维、粗蛋白、淀粉和粗脂肪的影响在不同品种间变化趋势不一致。综合生物产量和粗饲料分级指数,在黄淮海地区天泰366和登海605推荐种植密度分别为9×104株/hm2和11.25×104株/hm2,青农118和登海圣丰168推荐种植密度为9×104~11.25×104株/hm2。  相似文献   

2.
密度对青贮玉米产量和品质的影响   总被引:5,自引:0,他引:5  
以4个青贮玉米品种为试验材料,研究了4个种植密度对青贮玉米生物产量、干物质产量和品质的影响。结果表明:不同品种之间生物产量和干物质产量差异极显著;不同密度下品种的生物产量和干物质产量差异极显著;不同密度对不同品种品质影响较大,增加密度有助于青贮玉米品质的提高。青贮玉米品种的生育期、株高、穗位高、茎粗、收获期、绿叶数差异不大,品种间差异主要由品种自身特性决定。  相似文献   

3.
粮饲兼用型玉米青贮产量形成及调控研究   总被引:6,自引:0,他引:6  
朱霞  杨文钰  任万君 《玉米科学》2005,13(2):090-093
试验选用了在四川当地适合作青贮的粮饲兼用型玉米品种川单21、成单22、雅玉8号、燎原青贮玉米2号与从新疆引进的专用青贮玉米品种新青2号作对比试验,研究其产量形成规律及适宜的种植密度与收割时期。结果表明,鲜物质、干物质产量以及果穗产量均以粮饲兼用型玉米较高,其中以雅玉8号表现最优;适宜的种植密度为127500株/hm2;粮饲兼用型青贮玉米的适宜收获期在抽丝后35~42d,专用型青贮玉米新青2号在抽丝后28~35d。  相似文献   

4.
不同密度对青贮玉米产量与品质的影响   总被引:13,自引:5,他引:13  
青贮玉米不同密度下的子粒产量和品质测定结果表明,不同种植密度直接影响子粒的产量与品质,在一定的密度范围内,玉米子粒蛋白质、脂肪的含量在不同成熟阶段随密度的增加呈下降趋势。玉米子粒中蛋白质、脂肪的低含量与最高产量相对应,但玉米子粒中蛋白质、脂肪的高含量却不与较低产量相对应。  相似文献   

5.
总结粮饲兼用型、多叶型和棕色中脉型3种类型青贮玉米杂交种的特点。介绍青贮玉米产量和饲料营养价值的评价指标和方法,比较不同类型的青贮玉米种质资源的饲料营养价值和目前美国市场上最新的青贮玉米杂交种的农艺性状和品质性状。2010年美国德克萨斯州青贮玉米区域参试杂交种生物产量和干物质产量分别达78 210 kg/hm2和27 370 kg/hm2,淀粉含量平均为40.9%,中性洗涤纤维平均36.4%,总可消耗营养平均为75%。  相似文献   

6.
以登海605(DH605)、京农科728(JNK728)和山农饲玉2号(SY2)为试验材料,设置3个种植密度60 000株/hm2、75 000株/hm2和90 000株/hm2(记作D6、D7.5和D9),研究种植密度对不同夏玉米品种不同收获期及不同器官饲用和青贮品质的影响。研究结果表明,随着种植密度增加,DH605的鲜物质和干物质产量显著提高,D9密度下的鲜物质和干物质较D6分别增加17.32%和23.19%,较D7.5分别增加6.26%和7.13%;JNK728和SY2的鲜物质和干物质产量呈现先增加后降低的趋势。蜡熟期进行收获和青贮,玉米的饲用价值最高,以D7.5密度为例,DH605蜡熟期玉米粗饲料分级指数分别较乳熟期和完熟期增加8.31%和27.80%,JNK728分别增加12.55%和75.52%,SY2分别增加7.13%和58.10%;同时瘤胃降解率最高,各品种趋势一致。果穗青贮的饲用品质较秸秆青贮显著提高。本试验研究结果,DH605的最佳种植密度为90 000株/hm2,JNK728和...  相似文献   

7.
种植密度对青贮玉米品种产量及相关性状的影响   总被引:3,自引:0,他引:3  
以6个青贮玉米品种为试验材料,研究了3种种植密度对青贮玉米生物产量、干物质产量及相关性状的影响。结果表明,不同品种之间生物产量和干物质产量差异极显著;不同密度下品种的生物产量和干物质产量差异极显著;品种与密度互作之间生物产量和干物质产量差异分别为显著和极显著。龙育1号、高油169和高油115作为优质青贮高油玉米在黑龙江省适宜种植密度分别为7.0~8.0万株/hm2、7.0万株/hm2和6.0万株/hm2;黑饲1号在6万株/hm2时产量较高;龙辐208在7万株/hm2种植条件下,其生物产量和干物质产量均较高,尤其干物质产量最高;青贮玉米品种的青贮生育日数、株高、穗位、茎粗、收获期绿叶片数差异不大,品种之间差异主要由品种自身特性决定。中原单32可作为粒用玉米种植推广。  相似文献   

8.
密度及收割高度对复播青贮玉米产量和品质的影响   总被引:3,自引:1,他引:3  
以农大1027组合为材料,在大田条件下分别研究了5种密度及不同收割高度对复播青贮玉米(生长期82 d)产量和饲用品质的影响。结果表明:在密度6万~18万株/hm2范围内随着密度的增加产量先增后降,密度与产量呈二次曲线关系;而饲用营养品质却随密度增加呈现下降趋势。产量最高的密度和品质最优的密度不一致,优质时的密度显著低于高产时的密度。在密度9万~12万株/hm2条件下,可以获得产量高、品质较优的青贮玉米。适当提高收获高度可以明显改善青贮玉米的饲用营养品质。  相似文献   

9.
施钾对华北高寒区饲用玉米产量与营养品质的影响   总被引:1,自引:1,他引:0  
在冀西北高寒区旱砂地条件下,研究钾肥施用量对饲用玉米产量和营养品质、根系吸收能力的影响。结果表明,施钾肥显著提高了饲用玉米的生物产量,增产5.3%~27.7%;施钾肥降低了粗蛋白、粗脂肪、全磷含量,显著增加了粗纤维、粗灰分和全钾含量,增加幅度分别为6.9%、18.0%和85.9%,3个施钾肥处理生物累积量分别提高36.1%、50.4%和137.1%;施钾肥明显提高了伤流强度、各养分流量和钾离子浓度,其中,钾离子流量和浓度分别提高240.7%和42.9%,降低了茎基部伤流液中全氮和无机磷的浓度。均衡养分管理是提高饲用玉米产量及肥料效应的关键。  相似文献   

10.
施氮量对粮饲兼用玉米子粒产量和饲用品质的影响   总被引:1,自引:0,他引:1  
2017~2018年以主推粮饲兼用玉米陕科9号品种为材料,设0、90、180、270和360 kg/hm2 5个氮肥水平进行大田试验,测定不同氮肥处理下叶面积指数、产量和饲用品质和氮肥利用率等性状指标,分析施氮量对玉米子粒产量、饲用品质和氮肥利用率的影响。结果表明,随施氮量的增加,叶面积指数、SPAD值和生物量增加;子粒产量随施氮量的增加先增加后稳定,此时最佳施氮量为268 kg/hm2,产量增加64.4%。随着氮肥增加,氮肥农学效率呈先增加后降低,氮肥偏生产力降低。饲用品质分析显示,子粒蛋白质、淀粉和脂肪含量随着施氮量增加而增加,在氮肥270 kg/hm2处理下分别较不施氮处理增加2.4%、13.7%和22.5%;秸秆中性洗涤纤维和酸性洗涤纤维含量分别减少20.4%和18.1%,秸秆粗蛋白和体外干物质消化率分别增加22.5%和17.6%。适当增施氮肥改善玉米群体质量,增加产量和氮肥利用率,提高饲用价值。陕北灌区粮饲兼用玉米生产实践中,推荐适宜施氮量为268 kg/hm2。  相似文献   

11.
12.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

13.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

14.
15.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

18.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

19.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

20.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

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