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1.
基于DSSAT模型的河南省小麦生产潜力定量模拟与分析 总被引：4，自引：0，他引：4
为定量评估气候变化背景下河南省小麦生产潜力和增产空间的变化特征,应用DSSAT模型估算了河南省15个生态点连续50年(1963-2012年)的冬小麦光温生产潜力和气候生产潜力,并分析了生产潜力的分布规律。结果表明,河南省小麦光温生产潜力为8 350~9 996kg·hm-2,总体呈现北高南低、东高西低的趋势,而气候生产潜力为2 590~7 943kg·hm-2,总体呈现南高北低的趋势。河南大部分麦区光温生产潜力变化范围为9 173~9 446kg·hm-2,约占全省小麦总面积的43.5%。光温生产潜力高于9 447kg·hm-2的地区主要分布在豫北麦区(安阳、新乡西北部)及豫中麦区(许昌、西华),约占全省小麦总面积的33.6%。河南省大部分麦区气候生产潜力变化范围为4 375~7 050kg·hm-2,约占全省小麦总面积的59.5%。河南省15个地点的水分满足率为28%~91%,大部分地区水分满足率不到60%;河南小麦灌溉增产潜力变化范围为723~6 573kg·hm-2,其中三门峡、郑州、开封、商丘等地以北地区的灌溉增产潜力在4 623kg·hm-2以上,约占全省小麦总面积的49.4%,而驻马店以南及信阳地区的灌溉增产潜力低于2 673kg·hm-2,约占全省小麦总面积的17.5%。 相似文献
2.
甘肃中、东部地区春小麦产量潜力研究 总被引：1，自引：0，他引：1
根据甘肃中部、东部的气象数据,利用APSIM模型模拟研究区的春小麦产量,分析春小麦产量潜力。结果表明:甘肃中部康乐、临洮等地和甘肃东部泾川、灵台、合水、秦安等地的小麦产量实测值和模拟值误差较小,春小麦产量差较小,产量可提升的空间小;康乐县小麦产量的模拟值与实测值非常接近,小麦生产力接近于极限;定西、渭源、通渭、华亭、环县等地小麦产量实测值和模拟值之间差值较大,有较高的生产潜力。 相似文献
3.
施肥、密度和除草对半湿润地区冬小麦生物产量和籽粒产量的影响 总被引：6，自引：2，他引：4
为给旱作小麦高产栽培提供依据,在半湿润农田系统下以土垫旱耕人为土为供试土壤,研究了施肥、除草及种植密度对冬小麦生物产量和籽粒产量的影响.结果表明,除草对小麦生物产量和籽粒产量影响不明显;种植密度和施肥极显著影响小麦生物产量和籽粒产量;正常密度(播量150.0 kg·ha-1)的生物产量和籽粒产量比低密度处理(播量90.0 kg·ha-1)分别高15.5%和9.1%.相比不施肥、单施氮肥和单施磷肥,氮磷配施具有较高的增产效应.在一定范围内,增加施氮量有助于提高小麦的生物产量和籽粒产量,过量施氮有降低生物产量和籽粒产量的趋势.综合来看,在正常种植密度、氮磷配施和135kg·ha-1施氮量下,半湿润地区的冬小麦能获得较高的生物产量和籽粒产量. 相似文献
4.
《热带作物学报》2017,(10)
为了解贵州不同季节番茄气候生产潜力的变化趋势、空间差异以及番茄气候资源利用规律,研究基于贵州省81个气象站1961~2015年的气象资料,采用逐步订正、GIS空间插值和线性趋势分析等方法,分析番茄的光合、光温和气候生产潜力的时空变化特征。结果表明:冬春番茄的光合和气候生产潜力均呈递减的变化趋势,递减率分别为174.11、226.52 kg/(hm~2·10 a),而光温生产潜力为递增的变化趋势;夏秋番茄的光合、光温和气候生产潜力均为递减趋势,递减速率分别为355.24、317.99、427.67 kg/(hm~2·10 a);空间分布特征表明,冬春番茄的气候生产潜力空间上自东南向西部递减的趋势,夏秋番茄的气候生产潜力呈西南向东北递减的趋势;分别对番茄光合生产力分别进行温度、水分订正,冬春、夏秋番茄的平均气候减产率分别为35%、15%,其中降雨量是番茄气候生产潜力的主要限制因子。 相似文献
5.
为给小麦田间管理提供科学依据,以2000～2002年田间试验为基础,结合相关文献资料,借鉴R/WCSODS思路,建立了不同产量水平小麦最适总茎数动态模拟模型,利用济南与南京地区常年气象资料及相应品种参数等进行了检验.结果表明,在7 500 kg·ha-1产量时济麦19号和济麦20号在济南的最适总茎数动态模拟值与实测值的相关系数为0.9649～0.9690,差值标准误为154.2万～155.2万·ha-1,平均绝对误差为14.25万～127.5万·ha-1;在6 000 kg·ha-1产量时扬麦5号在南京的最适总茎数动态模拟值与实测值相关系数为0.9987,差值标准误为81.56万·ha-1,平均绝对误差为1.38万·ha-1.模拟值与实测值的相关系数均达显著或极显著水平. 相似文献
6.
为宏观了解冬小麦产量及产量稳定度的变化规律,基于1991-2013年黄淮海冬麦区91个有冬小麦种植的农业气象站点的冬小麦发育期及对应年份100个气象站点逐日气象资料,采用格点积温指标划分生育期,通过逐步订正法对冬小麦的气候生产潜力及其变异系数进行估算,之后结合国家气候中心RegCM3模式模拟A1B情景下1951-2100年0.25°×0.25°格点气象资料,对未来情景下冬小麦气候生产潜力及其变异系数进行预估。结果表明,从年际变化看,黄淮海冬麦区冬小麦气候生产潜力总体呈现波动下降的趋势,且该波动逐渐趋稳;各时段气候生产潜力基本介于6 277~7 044kg·hm~(-2),除2011-2040年有21.94kg·hm~(-2)·10a~(-1)的上升趋势外,其余时段均呈明显下降趋势。冬小麦气候生产潜力在空间上总体呈北部低、四周高,在时间上主要呈先平稳后逐渐降低的趋势;其变异系数在空间上总体呈北高南低,在时间上呈北部先增后减、南部先减后增的变化趋势。在实际生产过程中应更加注重冬小麦生长发育过程中光、温、水的匹配程度。 相似文献
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8.
施氮量对小麦旗叶光合速率和光化学效率、籽粒产量与蛋白质含量的影响 总被引：18，自引：8，他引：10
为给小麦高产高效栽培提供依据,在大田高产条件下,研究了施氮量对开花后小麦旗叶光合速率和光化学效率、旗叶和籽粒蔗糖含量及籽粒产量和蛋白质含量的影响。结果表明,适量施氮有利于提高灌浆中、后期的旗叶光合速率、旗叶PSⅡ实际光化学效率,以及灌浆末期旗叶PSⅡ最大光化学效率;施氮过多不仅不能继续提高旗叶光合速率,而且使PSⅡ实际光化学效率降低。施氮有利于提高旗叶蔗糖含量,促进灌浆前期籽粒中蔗糖的供应;施氮较多的处理中,灌浆后期有较多蔗糖滞留于旗叶中,致使施氮处理间籽粒蔗糖含量无显著差异。与不施氮的处理相比较,施氮105~195 kg.ha-1显著提高籽粒产量,施氮105~240 kg.ha-1显著提高籽粒蛋白质含量;继续增施氮肥至285 kg.ha-1,籽粒蛋白质含量、粒重和籽粒产量均降低。综合考虑籽粒产量和蛋白质含量,施氮量以150~195 kg.ha-1为宜。 相似文献
9.
灌水时期和数量对小麦耗水特性及产量的影响 总被引：7，自引：1，他引：7
为确定高产麦田的适宜灌水时期和数量,在池栽试验条件下,选用中筋小麦品种泰山23,研究了灌水时期和灌水量对小麦耗水特性及产量的影响.结果表明:(1)灌底墒水60 mm和拔节中期水30 mm的W1处理籽粒产量和水分利用效率较高,分别为7 727.10 kg·ha-1和18.69 kg·ha-1·mm-1,灌溉水利用效率最高.灌底墒水、拔节后期水和灌浆期水各60 mm的W5处理的籽粒产量最高,为8 494.50 kg·ha-1;水分利用效率与W1处理无显著差异.(2)W1处理和W5处理的总耗水量分别为413.46和464.91 mm;灌溉量、降水量、土壤贮水耗水量分别占总耗水量的比例为21.77%、41.43%、36.80%和38.72%、36.85%、24.44%,W1处理提高了对降水和土壤贮水的利用比例,而W5处理提高了对灌溉水的利用比例.(3)W1处理全生育期0～200 cm土层的土壤贮水消耗量最高,为152.16 mm,并且深层100～180 cm各土层的土壤贮水消耗量均显著高于其他处理,而W5处理全生育期0～200 cm土层的土壤贮水消耗量最低,为113.61 mm. 相似文献
10.
郑麦9023是河南省优质小麦生产的主导品种。为了建立郑麦9023的优质高效生产技术体系，对该品种品质特性在河南省的地域性变化以及土壤养分、氮磷钾肥料、杀菌剂对该品种品质特性的影响进行了研究。结果表明：(1)郑麦9023的品质特性在河南省的北部地区可稳定达到优质强筋小麦国家1级标准，在中部地区总体上接近优质强筋小麦国家1级标准，在南部地区可以达到优质强筋小麦国家2级标准；(2)抽穗期土壤速效N的含量是决定郑麦9023品质水平的关键栽培因素，此时土壤速效N含量60mg／kg、80mg／kg和160mg／kg分别为郑麦9023品质达到亚强筋、强筋、超强筋的土壤N素临界值；(3)K肥对强筋品质特性具有正效应，而P肥对强筋品质特性具有负效应；(4)杀菌剂粉锈宁对强筋特性具有劣化作用，而多菌灵无此负作用。 相似文献
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12.
《Journal of Crop Improvement》2013,27(2):81-114
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. 相似文献
13.
Lakshman Lal 《Potato Research》1987,30(2):329-334
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. 相似文献
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15.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
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. 相似文献
16.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
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. 相似文献
17.
Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
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 RXact). 相似文献
18.
Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
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. 相似文献
19.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
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. 相似文献
20.
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). 相似文献