甘蔗喷施旱地龙的效应研究

2005年,以甘蔗品种台优为试验材料,在甘蔗分蘖期和生长初期分别喷施不同浓度的旱地龙,通过测定甘蔗的农艺性状、产量性状、甘蔗糖分等指标,研究旱地龙对甘蔗生长、产量和品质的影响.试验结果表明:喷施旱地龙处理的甘蔗分蘖率、株高、生长速度、产量、蔗糖分均优于对照,其中3g/L处理对提高甘蔗分蘖率、前期生长速度和蔗糖分的效应最佳;4g/L处理对促进后期蔗茎生长、提高甘蔗产量的效应较好.喷施旱地龙后每667m2甘蔗产量比对照增长179-246kg,农民增收40.1-56.9元;11月～2006年1月平均蔗糖分以3g/L处理的表现最好,比对照高0.94个百分点.在不同浓度旱地龙处理中,3g/L处理的综合效应较好.     

硅肥不同喷施浓度对玉米抗倒伏性能及产量构成的调控效应

为探究硅肥不同喷施浓度对玉米抗倒伏性能及产量的调控效应,以先玉335为供试品种,比较分析灌浆期不同处理下玉米茎秆形态特征、基部节间力学特性及产量构成因素的差异变化。结果表明,叶面喷施硅肥对玉米株高、穗位高影响不明显,但可显著降低植株重心高度,以12 g/L浓度处理降幅最为显著,达6.02%;基部节间长度、扁平率则随着喷施硅肥浓度的加大而表现为逐渐下降趋势。喷施适宜浓度硅肥促进了茎秆机械强度的改善以及玉米倒伏发生风险的降低;叶面喷施适宜浓度的硅肥,对玉米产量和产量构成均有明显的促进作用。本试验条件下8～12 g/L为叶面硅肥最佳喷施浓度。     

套作遮荫条件下烯效唑对大豆壮苗机理的研究

为探明烯效唑在套作遮荫条件下对大豆的壮苗机理,通过盆栽试验,研究了烯效唑干拌种（0、2、4、8 mg/kg）对大豆苗期根、叶生理功能的影响。结果表明,烯效唑干拌种提高了根体积、根系活力和根系活跃吸收面积（除8 mg/kg）,但显著降低了根长。同时,烯效唑干拌种还提高了根、叶中超氧化物歧化酶(SOD)和过氧化物酶(POD)活性,从而降低了脂质过氧化程度,降低了根、叶中丙二醛(MDA)含量,提高了根、叶中脯氨酸(Pro)含量,最终保护了细胞膜的完整性和功能性,其中烯效唑干拌种浓度以4 mg/kg最佳。可见,适宜浓度的烯效唑干拌种可以改善套作大豆苗期生长,提高耐荫抗逆能力,有利于套作大豆后期的营养生长和生殖生长。     

钼酸铵拌种和喷施对大豆产量、品质和籽粒钼含量的影响

田间试验研究了钼肥拌种和花期喷施对大豆产量、品质及籽粒钼含量的影响.结果表明:各处理产量、蛋白质含量和籽粒钼含量都较不施钼肥的对照处理有明显的增加,且差异显著,只有籽粒脂肪含量增加不明显,各处理间差异不显著;比较不同施肥方式发现,拌种对大豆产量增加量大于花期喷施的增加量,但均没有拌种加花期喷施的增加量大,对蛋白质、脂肪和籽粒钼含量的影响也存在这种规律.     

烯效唑干拌种对大豆形态特征和产量的影响

以晚熟大豆品种贡选1号为材料,研究了烯效唑干拌种对大豆生长过程中的主要形态特征和产量的效应.结果表明：干拌种处理降低了株高,增加茎粗,缩短主茎长,增加了叶片数和分枝数,提高了叶片SPAD、叶面积指数和干物质积累,最终通过增加单株有效荚数提高了产量,以3.2 mg/kg浓度拌种的增产作用最大.     

黄土高原地区优良大豆根瘤菌的筛选与接种方式研究

采用蛭石和土壤盆栽试验,从黄土高原地区17个大豆品种上采集根瘤,对根瘤进行分离纯化、回接验证和遗传多样性分析,根据遗传多样性分析结果、分离宿主和分离地点,选出代表菌株用于筛选与黄土高原地区面积种植最大的大豆品种晋豆25相匹配的优良菌株,并在田间进行了根瘤菌喷施、拌种和种下接种不同接种方式效果比较试验.以瘤数、瘤干重、植株干重、植株全氮量为指标,通过蛭石盆栽试验初筛获得与晋豆25共生匹配效果好的根瘤菌10株;其进一步的耐旱试验和土壤盆栽复筛结果表明:菌株Bradyrhizobium liaoningense 4345和Sinorhizobium fredii 4338在结瘤能力、固氮能力、竞争能力和耐旱性能方面最好,揭示B. liaoningense 4345和S. fredii 4338具有良好应用前景.在田间进行的根瘤菌3种接种方式小区试验中,B. liaoningense 4345喷施处理在大豆植株干重、植株全氮量、占瘤率和产量等方面均显著高于另2个处理和对照,S. fredii 4338拌种和喷施较好,表明黄土高原地区大豆根瘤菌的适宜接种方式是喷施和拌种.     

化控栽培技术对大豆产量及其构成因素的影响

为明确化控栽培技术对大豆产量及其构成因素的作用,在大田栽培条件下,初花期进行叶面喷施2-N,N-二乙氨基乙基己酸酯(DTA-6)和烯效唑(S3307)试验,以喷施清水为对照.结果表明:喷施55 mg/L DTA-6和50 mg/L S3307,均可使大豆单株各部位的荚数、粒数明显增加;喷施55 mg/L DTA-6处理较对照增产758.71kg/hm^2.说明化控栽培对大豆产量及其构成因素具有显著促进作用.     

喷施烯效唑对玉米叶片衰老特性和产量的影响

以新品种川单418为材料,研究了在玉米抽雄期喷施烯效唑对玉米生长后期叶片衰老特性和产量的效应。结果表明,喷施烯效唑有效抑制了细胞膜透性物质的产生,促进叶绿素的形成,并改变了叶绿素动态变化规律,减缓叶片的衰老进程,提高作物产量。适宜喷施浓度为20～40 mg/L。     

“新美洲星”在大豆上应用效果简报

2017年采用"新美洲星"拌种和在大豆开花期及鼓粒期叶面喷施试验表明:可延长叶片功能期,提高大豆的株高、单株粒数、百粒重等性状,增加大豆产量10.8%~14.4%,并可减少播量1 kg/667m~2,以处理2最好,试验获得初步效果,尚待严格、科学的重复试验。     

锰对大豆氮代谢相关指标及产量品质的影响

以大豆品种垦农4号为材料,在大田小区试验的条件下,研究EDTA-Mn浸种和在初花期（R1期）叶面喷施对大豆叶片可溶性蛋白、硝态氮、游离氨基酸含量、硝酸还原酶活性及产量品质的影响。结果表明,无论在浸种处理（A）还是叶面喷施处理（B）中,中浓度锰(即A3 1.54g/L和B3 20g/L)处理对大豆叶片可溶性蛋白、硝态氮、游离氨基酸含量及硝酸还原酶活性均有一定的促进作用,但随着生育期的推进,浸种处理对各指标影响效果逐渐减弱。同时,中浓度的锰处理有利于大豆单株粒数、荚数和单株产量的提高,从而达到大豆增产的目的,且能够使大豆的蛋脂总量明显提高。高浓度的锰(即A4 15.4g/L或B4 60g/L)处理则对上述指标起抑制作用。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

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.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

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.     

Mineral composition of some traditional Mexican teas

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.     

Novel food and non-food uses for sorghum and millets

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.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

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.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

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 RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

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.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

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.