早稻直播覆膜旱作对灌浆成熟期根叶生理特性及产量的影响

 对早稻直播覆膜旱作与常规水作栽培对灌浆成熟期根叶生理特性及产量的影响进行了比较研究。与常规水作栽培水稻相比，直播覆膜旱作早稻千粒重显著下降，是导致产量明显下降的主要原因之一。而粒重的下降则主要归因于直播覆膜旱作较常规水作水稻灌浆成熟期根叶生理机能的衰退要快，表现为根系活力、叶片叶绿素含量、叶面积指数、净光合速率等下降较快，叶片超氧化物歧化酶、过氧化物酶等保护酶活性迅速下降，而丙二醛含量较高，使籽粒干物质积累受阻，揭示出提高灌浆成熟期根叶生理机能是进一步提高直播覆膜旱作早稻粒重和最终产量的重要途径。     

栽培模式对稻米品质特性的影响

以超级稻组合88S/1128和常规优质稻品种湘晚籼17号为材料,探讨了不同栽培模式(旱作覆膜、水作覆膜、旱作不覆膜、常规栽培等)对稻米品质的影响。结果表明,2个品种一致表现为旱作覆膜栽培的糙米率、精米率最高,水作覆膜栽培的整精米率最高;同一品种不同栽培模式的粒长和长宽比无显著差异,但覆膜栽培的垩白粒率、垩白大小更高。88S/1128旱作覆膜与常规栽培相比,直链淀粉含量降低、胶稠度变小、糊化温度升高;而湘晚籼17号旱作覆膜与常规栽培相比,直链淀粉含量降低、胶稠度变大、糊化温度降低。2个品种蛋白质含量表现一致,均为旱作不覆膜常规栽培旱作覆膜水作覆膜。稻米品质性状变异度最大的为外观品质,其次为蒸煮食味品质,碾米品质变异度相对较小。     

水稻旱直播技术在云南山区半山区的应用

水稻旱直播是一项轻简栽培技术,可节省大量劳动力,缓解劳动力季节性紧张的矛盾,具有广阔的应用前景。为探索水稻旱直播在云南山区半山区的最佳栽培技术,以楚粳27为材料,设置覆膜与氮肥用量2个因素,研究了覆膜与否及不同氮肥用量对楚粳27产量和生产效益的影响。结果表明,F12处理(覆膜,氮肥用量为180kg/hm2)综合表现最好,增产增收效果最佳。     

水稻覆膜直播旱作技术的特点及关键技术

客观评价了水稻覆膜直播旱作技术在农业科技创新、稻作理论与实践和节本增产增效方面的重要意义,提出了进一步优化水稻覆膜直播旱作技术的主要方法,明确了深化研究的相应举措。     

水稻覆膜水直播栽培技术

根据发展“节水农业”、“高效农业”和“轻型农业”的要求，我单位自１９９５年春季开始研究水稻覆膜水直播栽培技术及其机械设备，经过５年的不懈努力终于取得成功。水稻覆膜水直播的优越性是：①由于田面整体覆盖率在７０％左右，抑制了大部分地表水的蒸发。覆膜田实行湿润管理，可比常规种植的稻田节水５０％以上；②由于水直播墒情好，且均匀一致，播后出苗整齐。直播深度≤０．５ｃｍ，比插秧浅２．５ｃｍ左右。直播秧苗没有插秧苗的返青期，可连续生长。早春膜下地温比裸露田高１～３℃，能促早发，早分蘖，分蘖节位低，成穗率高，穗…     

不同栽培模式对超级杂交早稻株两优02生长发育及氮肥利用率的影响

研究了垄畦栽培、抛秧栽培、全程覆膜栽培、直播栽培、常规栽培模式对超级杂交早稻株两优02的生长发育和产量及氮肥利用率的影响。结果表明,与常规栽培（CK）相比,垄畦栽培分蘖成穗率高,LAI适中,齐穗后干物质积累量大,产量结构协调,产量和氮肥利用率高;抛秧栽培分蘖速率较快,分蘖和有效穗较多,齐穗期LAI较大,氮肥利用率较高,产量显著高于对照;直播栽培生育期明显缩短,LAI小,干物质积累量少,较对照减产显著。     

水稻机械覆膜穴播节水栽培

水稻机械覆膜穴播节水栽培是集地膜覆盖，节水栽培，幼苗旱长，机械直播为一体的综合配套高产，高效，节水栽培新技术，实践证明该法种植水稻亩产比旱直播增产１０％－２０％，增效５％－１０％，亩节水３００－６００ｍ＾３。     

夏直播花生覆膜高产栽培技术试验简报

１９９０－１９９３年在即墨市石门乡对夏直播花生覆膜栽培技术进行了较系统的研究与探讨，总结出一套成功的夏直播花生高产栽培技术措施。４年累计试验、示范面积达２０多公顷，平均单产花生英颗４４９５．５ｋｇ／ｈｍ＾２，比夏直播不覆膜每分顷增产荚果１３８０ｋｇ，增产４４％。     

覆草旱作对水稻主要农艺性状的影响及节水效应

为减小南方季节性干旱对水稻生长的影响,提高水分利用效率,于2003年在江西省余江县进行了水稻覆盖旱作的田间试验。大田条件下对比研究了裸地旱作、稻草覆盖旱作和常规水作下水稻大田生长期内的水分利用效率和作物主要农艺性状。结果表明,常规水作处理的灌溉水总量分别是裸地旱作和稻草覆盖旱作灌水量的2.42 和3.31倍。旱作处理下水稻的淹水时间明显减少,只有常规淹水处理的1/10左右。由于淹水时间的减少,水分渗漏量和田面蒸发损失也大大降低。旱作条件下,稻草覆盖旱作的水稻分蘖数、叶面积、根系生长明显优于裸地旱作。覆盖旱作产量最高可达6 747 kg/hm2,接近于常规水作对照的6 811.5 kg/hm2,两者无显著差异。而裸地旱作处理的水稻产量仅为4 716 kg/ hm2,显著低于常规水作和稻草覆盖旱作处理。水分利用效率和灌溉水利用效率均为稻草覆盖旱作>裸地旱作>常规水作。     

水分管理方式对水稻产量和氮肥利用率的影响

 以杂交籼稻汕优63和丰优香占及粳稻武育粳3号和9516为材料,研究了中期搁田、结实期干湿交替灌溉以及旱作对水稻产量和氮肥利用率的影响。结果表明,与水层灌溉相比,搁田处理显著提高了水稻产量。结实期干湿交替灌溉对水稻产量的影响因施氮量不同而有所差异。在常规施氮量（240 kg/hm2）下,干湿交替灌溉对水稻产量无显著影响,而在高氮（300 kg/hm2）条件下,干湿交替灌溉显著提高了水稻产量。水稻旱作与常规水作产量无明显差异。除武育粳3号外,中期搁田处理显著提高了汕优63和丰优香占的氮肥利用率;结实期干湿交替灌溉提高了高施氮量处理氮肥的农学利用率和生理利用率;水稻旱作有利于提高氮肥吸收利用率。     

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.     

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.     

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.     

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.     

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.     

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.