杂交水稻制种产业回顾及持续发展对策

中国通过近50 a杂交水稻制种技术研究与实践，先后形成了三系法和两系法杂交水稻制种技术体系及机械化制种技术体系，建立了一批具有生态优势的国家级杂交水稻制种基地，杂交水稻制种规模与技术一直处于世界领先地位。但目前尚存在制种组织管理模式欠规范、基地建设速度较慢、新技术推广迟缓，制种技术实施不及时、制种产量与种子质量不稳定等问题。为确保中国杂交水稻制种产业可持续高质量发展，提出以下对策：政企协调配合共同建设具有高标准农田与先进设施设备的专业化制种基地；严格实施种业企业基地准入制，完善制种经纪人资质管理；加强新组合制种技术研究，加快推广杂交水稻机械化制种技术，进一步规范制种风险保险。     

杂交棉制种适期及其制种效率的研究

利用杂交棉制种亲本花进程的Ｌｏｇｉｓｔｉｃ方程，参照制种地区的工资物价水平和气候条件，确定了江苏省淮北地区杂交棉制种的临界日的开花量指标为７４４１．８朵．ｈｍ＾－２．ｄ＾－１，制种适期为７月１２日到８月２０日。在制种适期内制种可以节省用工２７．５％，制种效率提高２３．４％。     

提高低温敏感型甘蓝型油菜雄性不育三系制种杂交率的途径

1990～1994年，以两个低温敏感型甘蓝型油菜细胞质雄性不育系为材料，探讨了提高制种杂交率的途径。结果表明：（1）在平丘区秋播制种条件下，不育系的不育度在70％以下，平均制种杂交率为62．0％，在自然生态条件下，难以筛选到秋播制种的适宜区域。（2）采用平丘区晚直播制种途径，不育系的不育度可提高到90％以上，但制种亲本个体发育不良，综合性状差，制种产量受影响。（3）高海拔区（2600～3200m）春播制种途径，其制种杂交率达93．0％以上，两年制种产量达到607．5～1939．5kg／hm2，平均1298．3kg／hm2，超过平丘区秋制水平。     

内江市杂交水稻高产制种的主要经验

在总结制种高产县经验的基础上，分析了内江市杂交稻春播夏制的几个主要技术问题，指出，保证种子纯度是高产制种的前提；改进制种技术，增苗增德是高产制种的保；提高异交结实率是高产制种的关键。     

培矮64S系列组合制种技术总结

根据４ａ制种实践，总结了培矮６４Ｓ系列组合制种的高产经验，即选择具有两系制种优势的基地，确定安全育性敏感期，选择最佳抽穗授粉天气，采取配套制种技术措施等。     

皖北地区玉米高产杂交制种技术研究

皖北地区过去被列为玉米杂交制种非适宜区。作者在分析以前杂交制种低产原因，本地区气象要素，总结周边地区高产制种技术的基础上，提出“皖北地区玉米高产杂交制种技术研究”课题。通过选用高产制种组合，调整播期，父母本错期、行比，增加母本密度，优化配方施肥等一系列技术措施，将本地区玉米杂交制种产量由过去的2250kg/hm²左右，提高到3750kg/hm²以上，实现本地区玉米杂交制种历史性突破，并提出4500kg/hm²玉米高产制种模式，     

我国杂交水稻制种的回顾与展望

在全面回顾我国杂交水稻制种发展历程的基础上，探讨了超高产杂交水稻制种的技术路线，为我国杂交水稻制种的发展和超高产制种策略的制定提供了理论依据。     

建好四大枝柱制种高产稳产：伏牛山区杂交籼稻制种高产经验

利用“四支柱”理论总结分析伏牛山区杂交籼稻制种经验教训，制定高，稳，低制种技术，指导制种，获得大面积连年高产，稳产。     

云南温光敏两系杂交小麦制种技术研究

为探索适于云南高原麦区的温光敏两系杂交小麦制种技术，以云杂3号（C49S-87／98YR5）、云杂5号（K78S／01Y1-1069）为材料，在1997-2005年大面积生产制种中，对与制种纯度和产量相关的主要技术措施进行了研究，制种实践及研究结果表明：父母本行比极显著地影响制种产量，云杂3号、云杂5号的最佳父母本行比分别为2：8和2：6；对于C49S-87，为确保制种纯度和制种产量，制种以利用前3个分蘖穗为宜；叶龄、叶枕距、幼穗长度等均可作为制种中预测父母本花期相遇的形态指标；不育系C49S-87和K78S的制种实践表明，不育系本身的育性参数和异交结实性对建立高效制种技术起决定性作用。2003年以来，已建立了一套基于K78S的简易、高效、低成本的温光敏两系杂交小麦制种技术，制种产量稳定在3750kg／hm。（不含该面积上的父本产量），制种纯度稳定达98％以上。     

杂交稻高产制种技术

大面积杂交稻制种单产如何稳定在250kg以上，高的达300～350kg，这是所有从事杂交稻制种的科技人员所希望的。制种是通过异交结实而获得产量，因此高产制种应围绕如何提高异交结实这一中心，笔者从1987年开始搞制种至今，经过不断的实践，对单产275～300kg（单产面积666．...     

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.