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1.
吉林省玉米高产田产量构成要素分析   总被引:3,自引:1,他引:2  
通过对吉林省玉米不同产量水平地块产量构成要素的分析,探讨了公顷穗数、穗粒数、百粒重、公顷粒数对产量的贡献和产量由低向高转变过程中产量构成要素的变化。根据产量构成要素对产量的贡献大小将不同品种类型分为增穗增产型、增穗和穗粒数增产型、增穗粒数和百粒重增产型、全能增产型等。提高玉米产量应根据产量构成要素的变化和品种的增产类型,相应的采取不同措施。  相似文献   

2.
土壤微生物对海岛棉生长及产量的影响   总被引:3,自引:0,他引:3  
对高产和一般产量海岛棉田土壤养分和土壤微生物数量进行了测定 ,并对两种产量棉田海岛棉生长和产量进行了调查。结果显示 :不同产量的棉田土壤养分和土壤微生物数量存在差异。由于土壤养分和土壤微生物数量不同 ,导致海岛棉生长势及产量的明显不同。同时提出了棉秆、油渣还田是海岛棉集约化种植条件下培肥土壤最为有效的措施  相似文献   

3.
利用光温敏两用核不育系广占63S分别和籼、粳型父本测交配组,通过对2种类型F1代的产量性状表现的比较,对2种组配方式32个F1组合的单株产量与产量性状的关系进行相关分析,并对产量性状对单株产量进行了通径分析。结果表明,广占63S与籼型父本配制的组合在结实率和千粒重上优势明显,其单株穗数和单株产量呈极显著正相关,结实率和单株产量呈显著正相关;粳型父本配制组合的结实率和单株产量呈极显著正相关,每穗粒数和单株产量呈显著正相关。2种组配方式后代组合产量性状对单株产量的直接作用也不相同,进而提出了利用广占63S与籼型材料配组比直接利用粳型材料配组更有利于选育出强优势实用型杂交组合。  相似文献   

4.
运用逐步回归、通径分析和相关性分析方法,研究了13个杂交棉品种中6个农艺性状对皮棉产量的影响。以及产量与产量性状间的相关性性。结果表明:单株果枝数、铃重和铃数对皮棉产量有显著的负向直接贡献,株高、衣分和籽指对皮棉产量均表现为显著的正向贡献。衣分与皮棉产量间的相关系数最大。  相似文献   

5.
黄萎病发病时间对棉花产量的影响   总被引:2,自引:0,他引:2  
为了研究黄萎病发病时间对棉花产量和产量组成因素的影响,以便为病害的综合防治和兼抗(耐)品种的选育提供科学依据,1984年我们进行了该试验,结果表明,黄萎病发病时间对棉花产量和产量组成因素影响  相似文献   

6.
依据1972—1983年本所丰产试验茶园的春茶产量资料和同期的气象记录,首先用正交多项式回归方法计算了春茶的趋势产量,再根据所分离出的气象产量,利用改进的费希尔(Fisher)积分回归方法分析了秋冬季气温、降水量和日照时数三个气象因子与翌年春茶产量的积分回归模式,并计算了各因子各时段对翌年春茶产量的影响系数。本研究利用数学方法定量地分析了秋冬季气象条件对翌年春茶产量的影响大小及原因,对提高春茶气象产量所应采取的栽培措施有一定的指导意义。  相似文献   

7.
遇旱灌水和施肥对大豆产量及农艺性状的影响   总被引:3,自引:0,他引:3  
于2008~2009年研究了遇旱灌水和不同施肥方式对大豆农艺性状和产量的影响.结果表明:遇旱灌水能显著提高大豆叶面积指数、生物产量、单株荚数、单株粒重和产量的不同施肥方式对大豆叶面积指数、生物产量、单株荚数、单株粒重和产量的影响表现为优化施肥>常规施肥>不施肥,并且灌溉条件下,不同施肥方式产量和产量相关性状差异更显著,表明灌溉在保证水份供应的同时,促进了肥料的吸收,起到了以水调肥的作用.  相似文献   

8.
氮肥不同追肥比例和时期对春小麦籽粒产量和品质的影响   总被引:23,自引:2,他引:21  
本文就氮肥不同追肥时期和比例对春小麦籽粒产量和品质的影响进行了研究.结果表明,产量、蛋白质产量及蛋白质含量均随追氮比例的增加而增加.综合产量和品质以追氮75%左右为宜.在追肥时期上,早追和重追分蘖肥对产量及品质均有不利影响,而孕穗期追肥可协调产量和品质的关系,使高产和品质能够有机的结合.  相似文献   

9.
为探明小麦品种‘扬麦11’在崇明东滩盐碱地栽培的高产群体茎蘖特征和产量结构,收集整理了2012~2014年的试验资料,分析不同产量类型的群体建成茎蘖特征和产量构成因素。结果表明,崇明盐碱地区‘扬麦11’小麦高产(≥6000 kg/hm~2)群体适宜基本苗和最高茎蘖数为预期有效穗数的0.40~0.46倍和2.4~2.7倍为宜,小麦群体成穗率40%以上;不同产量类型的产量构成因素对产量的贡献大小依次为:有效穗数实粒数结实率千粒重。高产小麦群体应在稳定适宜穗数基础上,提高结实率,以争取粒数为主攻目标。对不同产量类型中产量与产量构成因素进行统计分析,明确了产量与产量构成因素间的相关性存在明显的差异,这对获得不同产量类型目标的产量构成因素调控具有重要指导意义。  相似文献   

10.
水稻新品种试验是育种者筛选和鉴定选育品种和品种审定的关键环节,产量是衡量品种优势的重要指标。本文以湖南省水稻区域试验早稻组、一季晚稻组品种为材料,对试验产量结果进行分析,研究含水量对产量的影响情况。结果表明,含水量高低直接影响了各品种产量,两种计算方法的产量差异达显著水平,按照标准含水量来统一折算产量的方法能有效避免多种因素对产量的影响,真实地反映各品种产量情况。  相似文献   

11.
12.
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   

13.
14.
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   

15.
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   

16.
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   

17.
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.  相似文献   

18.
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   

19.
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.
Novel food and non-food uses for sorghum and millets   总被引:7,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   

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