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1.
不同株型玉米光能利用状况的研究   总被引:4,自引:1,他引:3  
利用美国LI-188B辐射量子照度仪,对掖单4号、掖单13和沈单7号3种不同株型玉米叶片及群体光能利用状况进行了测定研究,结果表明3种玉米品种叶片辐射吸收系数存在一定差异:掖单4号为0.75,掖单13为0.73,沈单7号为0.71。利用三次样条函数模拟了玉米群体中太阳总辐射及反射辐射分布状况,给出了不同品种玉米群体中吸收辐射随高度分布特征,发现在玉米叶片光合能力最大的80~180cm处,掖单4号吸收辐射最大,因而从理论上证实了紧凑型玉米品种光能利用效率最高,与当前高产实践相一致,并为玉米高产提供了理论指导。  相似文献   

2.
郭章贤  卢华兵  郭国锦 《玉米科学》2005,13(Z1):103-104
浙甜7号是浙江省东阳玉米研究所于2001年春以自选系美甜922111为母本,华L11111为父本组配而成的甜玉米单交种.各级试验示范结果表明:浙甜7号比浙江省甜玉米主栽品种超甜3号增产5%以上,且具有品质优、抗性强和适应性广等特点.在浙江省作春玉米和秋玉米种植,种植密度为49 500~52 500株/hm2。  相似文献   

3.
不同类型玉米饲用栽培物质生产特性研究   总被引:12,自引:2,他引:12  
试验于2001~2002年对三个不同类型5个玉米品种饲用栽培的物质生产特性进行了系统研究.结果表明各类型品种干物质积累量表现为科青1号>中单9409>东陵白>科多8号>掖单13,由于含水率不同,鲜物质积累量表现为科青1号>科多8号>中单9409>东陵白>掖单13,子粒产量粮饲兼用型玉米品种中单94∞与普通玉米品种掖单13无显著差异,但均大于青贮专用型玉米品种.干物质分配青贮专用型玉米品种以茎鞘较多,而粮饲兼用型及普通型玉米品种以子粒较多.  相似文献   

4.
为筛选适合浏阳市秋季种植的甜玉米新品种,对荟甜192、湘农甜玉2号、湘农甜玉3号和太阳王5号共4个甜玉米品种进行产量、生育期、农艺性状和田间抗性鉴定。结果表明,荟甜192、湘农甜玉3号适合浏阳市作秋玉米栽培。  相似文献   

5.
不同品种鲜食玉米的营养成分及抗氧化活性比较   总被引:2,自引:0,他引:2  
测定6个不同鲜食玉米品种的粗脂肪、蛋白质、淀粉、还原糖和总酚含量,对脂肪酸组成进行气相色谱分析。通过比较玉米浸膏的Fe~(3+)还原力和羟自由基(·OH)、超氧阴离子(O_2-·)、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率,评价其抗氧化活性,探讨抗氧化活性与玉米总酚的相关性。结果表明,鲜食玉米含粗脂肪6.17%~13.63%、蛋白质9.57%~15.30%、淀粉58.90%~69.52%、还原糖33.51%~42.12%、总酚1.52~2.68 mg/g。迪甜6号、晋超甜1号和超甜1825的粗脂肪、蛋白质、还原糖、总酚含量较高;京科糯2000、美玉糯13和都市丽人淀粉含量较高;美玉糯13饱和脂肪酸含量较高;晋超甜1号不饱和脂肪酸含量较高。超甜1825的Fe~(3+)还原力最强,迪甜6号清除·OH、O_2-·、DPPH自由基能力较强,抗氧化活性与玉米总酚含量呈正相关。  相似文献   

6.
粤甜15号为广东省农业科学院作物研究所于2004年以自育的品种粤甜11号为母本、日超-2为父本杂交培育的超甜玉米杂交种,经过2005年-2006年广东省甜玉米区域试验、大面积生产试验和示范,鲜果穗产量14554.5~15049.5kg/hm2、籽粒可溶性糖含量23.13%~29.62%、果皮68.7~73.1mμ,适口性专家评分90.9分,外观商品性佳,抗到中抗大小斑病和纹枯病,具有较大的推广价值.2007年通过广东省农作物品种审定.  相似文献   

7.
对几个夏玉米品种丰产性、适应性和稳定性的分析及评价   总被引:1,自引:0,他引:1  
采用回归分析的方法,对引进的几个夏玉米品种的丰产性、适应性和稳定性进行了分析.结果表明:掖单12、掖单4号及沈单7号表现较好,掖单13虽然高产,但稳定性较差.因此,在生产实践中,应按不同的生产水平和栽培条件,选择种植不同丰产性、稳定性的品种,以发挥其增产潜力.  相似文献   

8.
超甜玉米金菲于2004年5月通过上海市农作物品种审定委员会审定(沪农品审玉米2004第005号)。该品种属早熟类型.上海地区春播生育期83d左右,秋播70d左右.较对照粤甜3号早熟4~5d、  相似文献   

9.
紧凑型与平展型玉米的最佳收获期   总被引:5,自引:6,他引:5  
李芳贤  高谷  王金林 《玉米科学》1996,4(3):035-036
本文根据紧凑型玉米具有假熟性的特点,简述了紧凑型与平展型玉米的最佳收获适期。试验证明,掖单12、掖单13和掖单20等品种,其适宜的收获时间,为果穗白皮后的7~9天为其最佳适期。此时收获,公顷产量最高,试验表明,一般比对照增产10.58%~13.27%。若在果穗白皮时收获,则往往会导致玉米减产,减产率为9.75%~13.64%。而平展型玉米,如沈单7号、鲁玉6号和丹玉13等品种,其适宜的收获时间为完熟期。  相似文献   

10.
辽宁省部分玉米杂交组合品质性状的分析与评价   总被引:2,自引:1,他引:2  
对进入辽宁省区域试验的29个玉米杂交组合的粗蛋白质,赖氨酸,总淀,粗脂肪,容重等品质性状进行分析与评价,结果表明这些组合在蛋白质和赖氨酸含量上与掖单13号相比有一定的优势,在淀含量,容重等方面仍显不足。  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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