浅谈桃树矮化密植栽培的优点及原理

矮化密植栽培是现代果树发展的方向。该文介绍了桃树矮化密植栽培的优点及丰产的原理。矮化密植栽培之所以能优质、高产、高效益是由于充分利用了空间和土地,提高了桃园的覆盖率,树冠小,受光面大,光合效率高,光合作用强,同时采用了适于矮化密植栽培的技术措施。     

甜樱桃矮化砧木新品种Gisela的研究进展

甜樱桃矮化砧木新品种Gisela引入我国十多年来,已在多地进行了大量的试种比较试验及机理研究。为正确认识及推广应用该新品种,在多年科研的基础上结合目前种苗市场存在的问题,对该新品种的园艺特性、抗逆性、嫁接亲和性、苗木繁育及其缺点和栽培注意事项等作全面综述。     

芒果种植技术的改进

据根芒果的普及程度和种植面积来推测,它是印度最重要的果树.过去的芒果园多是实生树,产量低、果实质量差,果农收益少.种植芒果乃是名符其实的“展览馆”,只是用来迎合主人的个人兴致,而不是作为商业性的要求.可是,现在栽培芒果的观念改变了,甚至一般农民都发生兴趣,且在任何果园计划中都是重点考虑的.印度由于人口迅速增长,耕地面积大大减少了.工业化的要求,对于使芒果生产者在全国不同地区有意识地种植不同的品种,也有其一份贡献.为了提供芒果栽培的科学基础,有必要培育矮化品种或砧木,以利于密植,提高单产和方便果园管理.除培育矮化砧木和品种外,芒果还存在其它     

茶树矮化密植速成栽培技术

茶树矮化密植栽培,是一种高产栽培法。2001年在水北、三都、吴家塘等地试种6.7hm2获得成功,667m2干茶产量达282kg。而且矮化密植栽培能比常规栽培提早三年投产,产量高且增长快,经济效益显著。现将主要栽培技术介绍如下:1矮化密植茶园的建立1.1选好土地。凡土层1m以上,无铁锰硬结层,pH值4.5～5.5之间,地下水位低于1m,坡度10度以下的生荒地都可建园。熟地一般不如生荒地好。为避免水土流失,可先修筑梯幅等宽近似等高的梯田,再行开沟下肥作畦种茶。为避免根结线虫的为害,播种前,每666.7m2可用8.5kg3%的呋喃丹颗粒剂撒于播幅上,然后用铁锹将药…     

番荔枝种质资源收集评价和利用研究初报

对收集到的番荔枝科两个栽培价值较大的番荔枝属，果林果属９个种类，１９份种质材料进行了园艺性状，抗寒性，矮化性状及嫁接亲和性及亲缘关系进行了初步鉴定。评价。筛选出优质丰产品种Ａ．Ｐ进行推广利用。     

大樱桃砧木Colt试管苗芽增殖效果研究

[目的]筛选出大樱桃半矮化砧木Colt试管苗快繁最适培养基配方。[方法]以大樱桃半矮化砧木Colt试管苗为试材,研究植物生长调节剂、培养基无机盐浓度及蔗糖浓度对Colt砧木试管苗不定芽增殖的影响。[结果]培养基中添加0.5 mg/L BA,可促进芽增殖,增殖倍数为16.7;添加0.1 mg/L IAA时,其增殖倍数达19.1;1.0 MS无机盐浓度和30 g/L的蔗糖时,其增殖倍数分别为19.7和19.3。[结论]为大樱桃砧木其它品种快繁提供技术参考。     

棉花嫁接与高产栽培技术

棉花嫁接是选择抗病、生长旺盛、品质优良的海岛棉为砧木,选择生育期适中、桃多桃大、高产优质的陆地棉为接穗进行嫁接和栽培,以达到抗病、高产、优质的目的.2010年江苏省盐城市农业科学院采用改良劈接法对棉花进行嫁接,并示范栽培2 hm2以上,其成活率达到95%以上,一个熟练工每天可以嫁接300-500株;2011年盐城市天大农业技术公司开始产业化尝试,以合作社的形式为农民订单生产棉花嫁接苗,示范应用面积达到33.33 hm2以上.     

水稻示范园区高产栽培措施

总结了整地、育苗、插秧、施肥等高产栽培措施,以选择优质品种为前提,以适期收获为保证,为水稻高产、高效创造坚实的基础。     

浅述茶树矮化密植栽培技术

茶树矮化密植栽培技术,其所谓的“矮化”,就是以人为措施使茶树树冠高度比常规茶园树冠低1/3左右,也即树高控制在60～70cm;所谓“密植”,则是将单行条植改为多行条植,使每亩的株数比常规茶园多2～3倍。在土层深厚、土质肥沃的土壤条件下,选用良种采取矮化密植栽培,并加强茶园肥、培管理,可以达到茶树成园快、投产早和茶叶优质高产及经济效益提高的目的。笔者根据多年的生产实践,将茶树矮化密植速成栽培技术作一介绍。     

不同砧木对油亮型黄瓜品种生长、品质和产量的影响

用4种不同的南瓜砧木对油亮型黄瓜品种亮优王A、S4进行嫁接栽培,分析不同砧木对油亮型黄瓜的生长、品质和产量影响。试验结果表明：惠美一号砧木作为油亮型黄瓜砧木,可增强黄瓜植株长势,提高黄瓜产量,折算每公顷产量可达60 t以上,并且对其品质无负面影响。惠美一号砧木与S4组合为最佳嫁接栽培组合,其产量最高,瓜条大小匀称、光泽油亮、瓜柄短,商品价值高。     

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.     

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.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).