海洋细菌AiL3菌株防治香蕉枯萎病研究

采用室内盆栽和大田小区试验对海洋细菌AiL3菌株防治香蕉枯萎病作用及对香蕉的促生效果进行测定.结果表明:菌株处理后盆栽试验和大田试验中的香蕉苗叶片数、株高、光合速率和蒸腾速率等均明显高于对照;AiL3菌株盆栽试验处理6个月后对香蕉枯萎病的防治效果达100％,大田小区试验菌株处理8个月后对香蕉枯萎病的防治效果分别为72.71％和46.32％.表明AiL3菌株对香蕉植株有一定的防病促生作用.     

芒果炭疽病拮抗菌的筛选及防治效果研究

针对芒果炭疽病菌进行了拮抗菌的分离和筛选,并且采用有效菌株的发酵液进行了平板培养基抑菌试验以及采后芒果果实炭疽病防病试验。结果从24个菌株中筛选得到1株有效抑制炭疽病菌的芽孢杆菌M35,其抑菌圈大于13 mm,而且其发酵液对炭疽病菌也有明显的抑制作用;果实防病试验结果也显示,该菌株对于芒果采后炭疽病有显著的防治效果,且随着该拮抗菌菌悬液浓度的增加,防病效果提高,在浓度为l×l08 CFU/mL时,发病率为45%,病斑直径为14.1 mm。     

1.2%瑞拉菌素水乳剂防治小麦白粉病的效果

为了解瑞拉菌素对小麦白粉病的防治效果,用1.2%瑞拉菌素水乳剂在小麦田间进行不同喷施浓度、时间和次数试验。结果表明,在3个1.2%瑞拉菌素水乳剂喷施浓度(稀释600倍、700倍和800倍)中,600倍稀释液对小麦白粉病防治效果最好,防效达77.6%,保产作用为9.9%。从喷药次数看,用650倍的稀释液在小麦抽穗和扬花期喷施两次的防病效果最好,防效达74.4%,保产作用为10%;若喷施一次时,扬花期喷施的效果优于抽穗期喷施。     

小麦赤霉病拮抗性芽孢杆菌生防作用的研究

为探索小麦赤霉病生物防治的有效途径,对分离自中国东北嫩江小麦赤霉病流行地区小麦植株叶面和穗部的8株拮抗性芽孢杆菌进行了室内生物测定和田间小区防治试验.平板对峙培养、菌丝生长速率及孢子萌发测定等试验表明,8个菌株对小麦赤霉病菌的菌丝生长及孢子萌发均具有明显的抑制作用,其中以菌株B08的综合抑菌活性最强,其活菌体抑菌带宽达8.4 mm,无菌发酵液稀释5倍处理后96 h对菌丝生长抑制率为66.2%,处理分生孢子可使其完全丧失萌发能力,10倍稀释液可使孢子刚萌发的芽管膨大畸变而不能伸长,活体菌悬浮液和灭菌后的发酵液田间防效达59.5%～65.9%.发酵液热稳定性好,121℃、30 min加压蒸气灭菌后仍保持良好的抑菌活性.研究结果说明,供试拮抗菌株作为小麦赤霉病的生防材料具有很好的开发应用前景。     

7株拮抗细菌对蝴蝶兰叶基腐病菌的抑菌作用及其小区防效评价

以7株拮抗细菌对蝴蝶兰叶基腐病菌进行室内抑菌及小区防病试验。室内平板对峙法结果表明:以兰花内生枯草杆菌FJAT-9986的拮抗作用最强,其抑菌率为61.90%;JK-2抑菌率为50.44%;FJAT-8769的拮抗作用最弱,抑制率仅为34.09%。抑菌圈法复筛测定结果表明,菌株JK-2对蝴蝶兰叶基腐病菌的抑制作用最强,其抑菌圈直径为22.42 mm。拮抗细菌对病原菌孢子萌发实验结果表明,稀释50倍后,JK-2显示出强的抑制病原菌孢子的萌发作用,对蝴蝶兰叶基腐病的田间防效为76.7%,表明JK-2可作为田间防治的菌株。     

稀土旱地宝在马铃薯上的应用效果

马铃薯专用型稀土旱地宝在宁夏南部干旱区对马铃薯刀切种薯浸种试验结果表明,试验设计的3种不同浓度稀释液浸种20～30 min可使马铃薯比对照提早出苗3～5 d,提前成熟3～10 d,株高增加3.5～12.0 cm,产量增加3.4%～19.9%,并能有效预防早疫病、晚疫病、环腐病等细菌性病害。在3种不同浓度稀释液中,以25倍和50倍稀释液浸种防病抗旱增产效果显著。     

除虫灵室内防治荔枝蝽蟓初报

介绍新制药剂(正在开发中,暂命名为除虫灵)对荔枝蝽蟓卵、若虫、成虫室内药剂防治效果和室内药效试验的初步情况。稀释10倍液、20倍液和40倍液三种稀释液,采用手持型喷雾器喷雾。结果使用10倍液、20倍液和40倍液的成虫和若虫48h后全部死亡,使用10倍液和20倍液杀卵率为76.50%和72.57%,取得较好效果;药效试验采用3d、5d和8d三个药效时间,结果5d的药效杀虫率仍可达67.10%。     

不同剂型嘧菌酯防治芒果炭疽病的田间药效对比试验

以芒果炭疽病为试验靶标,测定50%嘧菌酯WDG和250 g/L嘧菌酯SC的田间防效。结果表明:3次药后10天(采收期),50%嘧菌酯WDG 250 mg/kg和166.7 mg/kg两种处理的防效分别为为72.16%和63.19%,对芒果炭疽病具有较好的防治效果。对照药剂250 g/L嘧菌酯悬浮剂有效剂量166.7 mg/kg处理的防效为64.91%,两种剂型在相同剂量处理间差异不显著。     

种衣剂沿江3号防治棉苗病害及对棉花生长发育的影响

通过室内活性测定及田间小区试验，证明种衣剂沿江３号对立枯病的毒力效果略高于该地区常用的灵福种衣剂，对炭疽病的毒力效果则明显高于灵福种衣剂。棉子使用沿江３号包衣后，出苗率接近于对照，死苗率低于对照，防病保苗效果及成钵率均高于对照药剂灵福种衣剂、炭枯净拌种剂     

几种新杀虫剂对棉盲蝽的室内药效试验

 将24%螺虫乙酯、80%丁醚脲、10%阿维·氟酰胺、20%氯虫苯甲酰胺、10%乙虫腈几种新杀虫剂按药剂包装上标定的稀释浓度对棉盲蝽进行室内药效试验筛选,结果显示：10%乙虫腈SC 750倍防效最好,药后1～3 d防效与80%氟虫腈WG 15000倍相当;20%氯虫苯甲酰胺SC 3000倍防效最差;24%螺虫乙酯SC 1500倍、80%丁醚脲WP 2500倍、10%阿维·氟酰胺SC 1000倍药后3 d均能达到较好的防效。     

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.