不同类型土壤对早籼稻产量性状的影响

试验于2004年在中国农业科学院衡阳红壤实验站进行。采用冲积土、板页岩、紫色土、石灰土和红壤及4个早籼稻品种：湘早籼24、湘早籼31、湘早籼32和湘早籼33,研究了土壤因素对早籼稻产量性状的影响。结果表明：土壤因素和品种遗传特性共同影响早籼稻的产量性状。千粒重、每穗总粒数、穗数和小区产量受遗传因素的影响大于土壤因素,结实率则相反;实粒数主要受土壤因素的影响。在紫色土中,早籼稻千粒重、实粒数、结实率和穗数均显著高于其他土壤的,但每穗总粒数最低。石灰土的早籼稻每穗总粒数较高,但千粒重、实粒数、穗数和结实率显著低于其他土壤的。红壤的早籼稻实粒数和穗数比较高,每穗总粒数、千粒重和结实率居中。板页岩的早籼稻每穗总粒数显著高于其他供试土壤,实粒数较高,千粒重、结实率居中,穗数比较低。冲积土的早籼稻结实率、千粒重和穗数较高,每穗总粒数和实粒数较低。     

分蘖时期及秧苗带蘖数与中稻——再生稻农艺性状的关系

秧田至本田３０天内分蘖，发生时间愈早，头季稻平着粒数、实粒数、结实率和单株产量均愈高；单茎再生苗、穗数和穗平着粒数、实粒数、结实率均依次增加或呈上升趋势。移栽苗带蘖数（在５－６个以内）与头季稻单株苗、穗数及产量的均是正相关，而与齐穗期、穗平着粒数、实粒、结实率则均呈负相关；与再生季的单再生苗数、穗平实粒数、结实率均呈正相关，但与单茎再生苗数、穗平着粒数却呈负相关，显示了早生分蘖和多蘖壮秧在头、地两     

稻米品质与水稻部分生育性状的相关研究

对水稻的经济性状和穗部性状与稻米品质性状进行相关分析，结果表明：出糙率与生育天数和株高有较大的负相关；垩白大小与生育天数呈正相关，与单株的生物产量和谷重呈负相关；粒宽与生育天数、株高和单株草重有较大的负相关，与单株谷重有较大的正相关；胶稠度与生育天数和株高有较大的正相关。糙米率与千粒重呈显著正相关；垩白率与每穗实粒数呈显著的负相关，与结实率、秕粒数、一次枝梗数呈显著的正相关；垩白大小与穗数、每穗实粒数、二次枝梗数呈显著正相关，与千粒重、结实率、每穗秕粒数呈显著的负相关性；垩白度与每穗实粒数、千粒重呈显著负相关，与每穗秕粒数、二次枝梗数、一次枝梗数呈显著的正相关；透明度与穗数、秕粒、结实率、实粒、千粒重都有较大的相关性。各穗部性状与直链淀粉含量和胶稠度的相关性不显著。回归分析表明，品质性状与水稻的其它性状间有着复杂的线性关系。     

粳稻主要农艺性状的灰色关联度分析

应用灰色关联度分析法对6个水稻品种的单株产量及主要农艺性状的关系进行了分析。结果表明:其主要农艺性状对单株产量的关联度从高到低依次为结实率单株有效穗每穗实粒数穗粒数穗长千粒重株高。因此,在水稻高产育种中,应注重对结实率、单株有效穗、每穗实粒数的选择。     

不同种植密度下小麦主要性状与产量和蛋白质含量的灰色评判

为了明确不同种植密度下小麦主要性状与产量和蛋白质含量的关系,以4种种植密度下4个小麦新品系(种)的11个性状为指标,运用灰色关联度分析其主要性状对产量和蛋白质含量构成的影响.结果表明,在不同密度下各主要性状对产量的关联度从大到小依次是:穗长＞可孕小稳数＞穗下节长＞株高＞蛋白质舍量＞整齐度＞不孕小穗数＞成穗数＞穗重＞千粒重＞穗颈长.在不同的密度下各主要性状对蛋白质含量的关联度从大到小依次是:株高＞可孕小穗数＞穗重＞千粒重＞穗长＞整齐度＞产量＞穗下节长＞不孕小穗数＞成穗数＞穗颈长.表明不同种植密度下影响产量和蛋白质含量的主要性状各有侧重,在高产优质新品种选育中应重视可孕小穗数和株高这两个主要性状.     

杂交中稻群体数量与质量性状关系的研究

 以杂交水稻组合80优121（中粳）和协优57（中籼）为材料,进行栽插密度试验,以培育数量和质量不同的群体,研究群体数量与质量的关系。试验结果表明,基本苗数、最高茎蘖数等群体数量性状之间和分蘖穗率、茎蘖成穗率等群体质量性状之间都呈正相关。群体数量与质量性状之间呈负相关,其中基本苗数与分蘖穗率、最高茎蘖数与茎蘖成穗率、总颖花数与结实率、有效穗数与平均穗谷重4对性状间相互关系最密切。在试验条件下,有效穗数、平均穗谷重、总颖花数和结实率对产量的直接作用较大,因此高产栽培需在适宜穗数和总颖花数的前提下提高结实率和平均穗谷重。     

使食味与产量并举要掌握新的生育(五)

４由茎数为主向成熟为主的稻作发展４．１关键是颖花数不如成熟率单位面积产量，由穗数、每穗颖花数、结实率、粒重组成。为了增产要增加颖花数，但增加必要的颖花数，是增加分蘖增加穗数，还是穗数少些而１穗颖花数多些，都必须考虑成熟好坏，结实如何。一般水稻有产７００kg左右的颖花数，但结实率８５％时产量实收为６００kg，若低于７０％，碎米增加，产量约为５００kg，以受光态势决定的成熟良否，对产量、米质影响很大。成熟良否，由出穗前１５日左右到完熟期淀粉生产的受光量和保持稻体健壮促进成熟的根的功能所决定。到生育后半期，…     

杂交水稻制种高产栽培技术

（一）制种高产的穗粒结构特点杂交水稻制种高产的基础是父母本具有理想的穗粒结构。制种产量的构成因子是父本穗花数×母本穗花数＋母本实粒数＋粒重。人们所需要的是母本产量，母本产量又是通过异交结实而来。因此，杂交水稻制种高产的穗粒结构具有以下特点。首先，要保证父母本足穗足花。不同产量水平父本德花数、母本穗花数、母本实粒数的变化是不同的（表1）。一般从低产到高产主要是增苗增穗；从高产到更高产，则在一定苗穗的基础上主攻异交结实率。其次，父母本之间穗花数有一个合理协调的比值（即颖花比）。父本的颖花数对母本的结…     

克丰6号小麦高产施肥技术及增产途径的研究

通过对克丰６号小麦新品种施肥对产量的效应及其对农艺性状变异的影响和相关性研究，结果表明：（１）克丰６号小麦新品种，平均单产５１４１．６ｋｇ／ｈｍ２，若栽培技术得当，公顷产量可达５９５８．０ｋｇ；（２）施肥对该品种农艺性状的变异影响大小顺序为：穗粒数＞无效小穗数＞有效小穗数＞株高＞千粒重＞容重．这表明增加有效小穗数，减少无效小穗数，增加穗粒数是施肥提高产量的关键；（３）从相关关系看，除千粒重和株高外，施肥与穗长、有效小穗数、穗粒数呈显著正相关，与容重呈显著负相关，与无效小穗数呈极显著负相关。     

影响水稻产量的主要性状因素试验研究

用常规粳稻松辽122与吉玉粳品种为试验材料在北方稻区早粳晚熟生态区域,连续3 a多点试验,研究其穗的长短、实粒数的多寡、千粒重的轻重等构成产量的遗传特性对参试品种产量的影响。结果表明:产量与有效穗数、穗实粒数、结实率的遗传特性,经数理分析,无论是单相关还是偏相关均达到显著和极显著水平。而穗长不等于穗粒多,由此得知丰产性好产量高的水稻品种,主要源于分蘖力强,有效穗数多,成穗率高,穗实粒多,结实率高。     

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.     

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.