BABA处理对采后芒果果实抗病性的影响

以‘台农1号’芒果为试材,研究采后分别用0、50、100、200、400 mg/L的β-氨基丁酸(BABA)处理对在常温（22～25 ℃）贮藏条件下芒果果实抗病性的影响,并探讨相关防御机制。结果显示,与对照果实相比,BABA采后处理显著降低了芒果果实的病情指数和病果率,从而提高了芒果的商品果率,对芒果采后抗病性具有明显的诱导作用,其中100 mg/L的BABA处理效果最好。在贮藏过程中,BABA(100 mg/L)处理不仅显著提高了芒果防御酶苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)的活性,同时也提高了芒果抗性物质总酚和木质素的含量以及贮藏早期过氧化氢（H2O2）的水平。表明防御酶、抗性物质及活性氧可能参与了BABA诱导芒果果实采后抗病性的过程。     

水杨酸结合超声波处理对芒果采后抗病性的影响

探讨水杨酸结合超声波处理对芒果采后炭疽病的抗病性及其相关防御酶活性的影响。以绿熟‘贵妃’芒为试验材料,用水杨酸(2 mmol/L)、超声波(40 kHz,500 W)单独处理及两者结合处理,贮藏24 h后进行损伤接种芒果炭疽菌(Colletotrichum gloeosporioides),并在接种后第6天测定病原菌的致病性;同时,对处理后未接种果实,每2 d取样一次,测定果肉组织中苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、几丁质酶(CHT)和β-1,3葡聚糖酶(GLU)等相关防御酶的活性和果皮中总酚含量的变化。结果表明:水杨酸能有效抑制芒果采后炭疽病病斑的扩展,能够提高相关防御酶的活性和果皮中总酚的积累;水杨酸结合超声波处理显著提高水杨酸单独处理的作用效果,显著增强了果实抗病性,是芒果采后炭疽病防控的新技术。     

采前BTH处理对芒果果实抗病性的诱导

以‘台农1号’芒果为试材,研究采前分别用1、50和100 mg/L苯并噻重氮（BTH）喷施处理对芒果果实抗病性诱导效果的影响。结果表明,与对照果实相比,100 mg/L BTH处理果实采收时的病果率、采后未接种果实的病情指数和接种果实的病斑直径显著降低,降低幅度分别为52.60％、54.30％和7.06％;并且在贮藏过程中,BTH处理果实中的苯丙氨酸解氨酶（PAL）、过氧化物酶（POD）和β-1,3-葡聚糖酶（GLU）的活性明显高于对照;另外,在贮藏前期（0~6 d）,BTH处理能够抑制芒果过氧化氢酶（CAT）的活性,提高芒果过氧化氢（H2O2）的含量。     

不同品种芒果块液氮速冻-解冻后质构特性比较研究

为评价不同品种芒果块液氮速冻后的品质特性,以桂热、金煌、凯特、紫花、红象牙等10个广西芒果品种为对象,对其速冻-解冻前后样品的开裂率、感观品质、色度以及硬度、凝聚性、弹性、咀嚼性等质构特性进行测试。结果表明,经液氮速冻后,10个品种芒果块的感官品质均有所下降,90%芒果品种出现开裂现象,硬度、咀嚼性下降幅度较大,色度、凝聚性、弹性下降幅度相对较小;其中桂热10号、金煌芒、紫花芒3个品种在液氮速冻-解冻后保持相对较高的品质。说明液氮速冻对不同品种芒果块品质的影响不同,本研究为液氮速冻应用于速冻芒果的加工提供理论依据和技术支持。     

10个棉花品种（系）田间人工病圃黄萎病抗性稳定性分析

 2006－2008年以感病品种鄂荆1号为对照,在人工黄萎病圃对10个陆地棉品种（系）进行了黄萎病抗性鉴定。以相对病情指数评价各品种的抗病性,共鉴定出3个高抗品种、2个抗病品种、2个耐病品种和2个感病品种。其中NJ0703、NJ0705、中植棉KV1的发病株率小于20%,病情指数小于10.0,抗黄萎病性达到抗至高抗水平。生物统计分析表明,各品种3年间的相对病指无显著差异,抗病性稳定。     

芒果炭疽病生境生态位

芒果炭疽病是海南省芒果生产中危害最严重的病害。本文应用生态位理论,测定芒果炭疽病生境生态位。结果表明芒果炭疽病的空间生态位宽度指数比较大,对空间资源利用较充分。果园中间的果树通风性差,湿度大,芒果炭疽病的病情指数最大,北边边线较通风、湿度小芒果炭疽病病情指数最小。果实期、夏稍期、秋稍期、花期芒果炭疽病的生境生态位宽度指数依次为：0.950 8、0.941 2、0.965 3、0.849 7。在各生境位点上,芒果炭疽病对资源的占有和利用能力是不同的,边线的生境相对不利于芒果炭疽病的生存,花期时果园各方位生境     

谈谈我省芒果生产的问题及措施

芒果已是漳州创汇农业区富有南亚热带特色的重要水果之一。目前云霄、诏安、南靖、安溪等四县的种植面积均超万亩。本文试图就漳州市南部的芒果商品性生产提出一些粗浅见解，以探讨不是芒果最适宜区的我省如何健康地发展芒果商品性生产。一、我省芒果生产存在的问题1、品种杂乱我省芒果传统植区以白花芒、红花芒二品种为主，这二个品种风味好，但可食率少、纤维多、产量也较低。这几年引进的秋芒，品质较好，产量中，但外观差，易感病;紫花芒丰产稳产，外观好，但品质中等；此外，还有桂香、桂热10号、斯里兰卡811、串芒、绿皮、青皮、象牙…     

茉莉酸甲酯处理对采后芒果果实抗病性的影响

以"红芒6号"芒果为试材,研究用0、1、10和100μmol/L的茉莉酸甲酯(Me JA)采后处理对芒果果实在常温(22~25℃)贮藏期间抗病性的影响,并探讨其与相关防御酶和抗性物质的关系,为寻找控制芒果采后病害的新技术提供理论依据。结果表明,采后Me JA处理显著降低了贮藏期芒果的病情指数和接种炭疽病菌芒果的病斑直径,其中以10μmol/L Me JA的处理效果最好。并且Me JA(10μmol/L)处理显著促进了贮藏期接种炭疽病菌芒果果实内源乙烯的释放,提高了防御酶苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)的活性以及抗性物质总酚和木质素的含量。这些结果表明,内源乙烯、防御酶和抗性物质可能参与了Me JA诱导的芒果采后抗病性的过程。     

海南主要芒果品种的模糊聚类分析

根据芒果的叶片性状变量(包括叶形、叶长、叶宽、嫩叶颜色和叶缘等5个方面),对海南22个芒果主栽品种运用模糊聚类的方法进行分析。结果表明:第1类芒果品种包括吕宋、台农1号、白玉、椰香、青皮、紫花、粤西1号、桂香芒、广西红芒、三年芒、龙眼香芒、桂热10号共12种;第2类芒果品种包括白象牙、海南土芒、海豹、金煌、黄象牙芒、扁桃芒共6种;第3类芒果品种包括云南小芒、红象牙、兴热1号共3种;第4类芒果品种包括黄玉芒1种。这与前人用其它方法分类的结果类似。分类结果可应用于芒果品种的识别与选育。     

3个品种杧果的叶片组织结构观察

从解剖学角度观察和分析了爱文、贵妃、紫花等3个品种杧果(芒果)的叶片组织结构。观测数据的统计分析结果表明：3个品种杧果的气孔密度、上表皮厚度、栅栏组织厚度、海绵组织厚度和叶片厚度间差异极显著,其中贵妃杧的气孔密度、上表皮厚度、栅栏组织厚度、海绵组织厚度和叶片厚度均为最大;3个品种的叶片气孔密度、气孔长度、气孔宽度的变异系数均较小,表明其气孔的密度尧长度和宽度是比较稳定的性状,因而可用作品种鉴定的指标。     

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.