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1.
中国野生大豆(G.soja)脂肪含量的多样性及地理分布   总被引:5,自引:2,他引:5  
徐豹  李福山 《大豆科学》1993,12(4):269-274
根据原产中国各地5147份野生大豆种子的脂肪含理分析结果,发现:1.脂肪含量与百粒重呈极显著正相关(r=0.9404^***)。2.4162份野生型(百粒重≤2.5g)脂肪含量为9.23%,542份半野生Ⅰ型(百粒重2.51-5g)为13.01%,443份半野生Ⅱ型(百粒重>5g)为15.23%。3.野生型脂肪含量与原产地经度(°E)呈显著负相关(r=-0.8862^***),与原产地纬度呈单峰曲  相似文献   

2.
泾阳棉区棉花产量与光温因素的通径分析   总被引:1,自引:1,他引:1  
分析表明,泾阳棉区皮棉单产与6月份的平均气温呈显著正相关(r=0.74*);与6月份日照时数呈显著正相关(r=0.78*);与8月份的平均气温呈极显著正相关(r=0.84**);5~9月份的降雨对泾阳棉区棉花高产属不利因素。通径分析结果,8月份的平均气温对皮棉产量的直接影响最大(dy·x2=0.343942);6月份的平均气温通过8月份的平均气温对皮棉产量产生的间接影响(dy·x1x2=0.149314)和6月份的平均气温通过6月份的日照时数对皮棉产量产生的间接影响(dy·x2x3=0.148065)相似,且都较大。  相似文献   

3.
通过标准加湿处理、手工脱粒种子发芽情况及落粒数的测定,研究了白粒小麦耐穗发芽能力的选择效果。降雨模拟器在促使群体平均值向高耐性水平漂移中是有用的,但在防雨条件下较大的基因型×年份工作使得对单个基因型未能作出准确的估计。最准确的估计是利用落粒数(t2=80.7%)和手工脱粒种子的发芽情况(t2=38.4%)得出的结果,这里没有基因型×年份的互作。种子休眠与降雨器中处理3天的落粒数的变化显著相关(r=-0.56)。在1992年的模拟降雨试验中,穗发芽指数与种子休眠试验指数不相关(r=0.20),但在1993年的发芽试验中,这两个指数间则为强相关(r=0.73)。在相同试验各年份的比较中,落粒数(未作降雨处理)和种子休眠指数两年间的相关系数分别为r=0.68和r=0.9,而两年间的穗发芽指数无相关(r=-0.03)。  相似文献   

4.
初步研究表明,具有相同遗传背景的无短绒陆地棉光籽(包括其杂种分离类型,与正常有短绒棉籽相比,籽棉减产8.05%~18.55%.皮棉减产20.92~22.51%.光籽与皮棉产量呈高度负相关。(r=-0.7364).与表分呈显著负相关.(r=-0.9642);与铃重呈高度负相关(r=-0.7092);与纤维细度。断裂长度、生育期均呈中、高度负相关(r分别为-0.7963、=0.6725、=0.7786)。籽致使品种纤维产量和品质迅速下降,是品种退化的重要原因之一。  相似文献   

5.
研究结果表明,在被测定的12种甜菜土壤养分含量中,有10种养分含量低于对照(麦地).其中,碱解氮,有效镁和有效锰的差异较大,其差值分别为26ppm、11.5ppm和7.4ppm,其余差异不大;在甜菜营养生长期内,分别测定了甜菜与对照土壤的微生物总量、细菌、放线菌和真菌的数量及消长动态;土壤碱解氮含量和耕层地温对细菌数量有一定的影响;甜菜土壤的3项酶活性均低于同期的对照。在甜菜吸收氮素的高峰期,土壤中脲酶活性亦明显增强,达到1.22NH_3-Nmg/g土。在幼苗期至糖分积累期,磷酸酶活性与甜菜苗龄呈正相关关系(r=0.9223 ̄*)。  相似文献   

6.
本研究目的是确定春小麦改良高产与高蛋白的选择指标。选用的8个品种中,6个表达为对照水平,2个品种UM632和UM684表达为通常高于对照的水平性状。试验2年中,不同重复的植株从花期至成熟进行取样测定,收集有关N、干物质积累及重新代谢的资料。籽粒蛋白含量与籽粒产量不相关,但与花后N吸收(r=0.66)、成熟期总植株N(r=0.49)及N收获指数(r=0.87)呈正相关,与成熟期营养器官N呈负相关(r=—0.49)。籽粒产量与花后N(r=0.50)和干物质量(r=0.77)以及收获指数(r=0.83)呈正相关。籽粒蛋白产量与花后N积累(r=0.90)、成熟期总N(r=0.98)、N收获指数及经济指数(r=0.93)呈高度相关。UM632和UM684将花后N吸收和成熟期总N量高与高度代谢效率及N收获指数结合在一起,故此可以得出结论:遵循构建成熟期总N量高、N收获指数及经济指数高的杂交组合,通过群体中选择籽粒蛋白产量可以逐步改良具有高产和高蛋白含量的品种。  相似文献   

7.
不同施氮水平对甜菜地和休闲地土壤微生物数量的影响   总被引:2,自引:0,他引:2  
本文比较了不同施氮水平对甜菜种植地和休闲地土壤中好气性细菌、放线菌和真菌数量的影响,并对土壤中的硝化细菌进行了测定。试验表明,氮肥能增加土壤中好气性细菌和硝化细菌的数量,并显著增加30~60cm土层中亚硝酸细菌数量,对5~10cm、10~30cm和30~60cm土层中的硝酸细菌表现出促进作用。各施氮水平的土壤微生物总数达1×10 ̄8个/g干土以上。其中细菌为主要类群,约占90%以上,其次为放线菌和真菌。在甜菜定苗前和收获期,5~30cm土层中微生物总数顺序为施用N_(120)>N_(180)>N_0,与甜菜的产量呈极显著正相关(r=0.928).  相似文献   

8.
通过药剂筛选和药剂剂量选择试验研究。15%多效唑可湿性粉剂按种子量2‰拌种;50%粉锈宁可湿性粉剂按种子量0.3‰拌种,80%402乳油按种子量0.5‰拌种;预防啤麦条纹病相对防效分别为100%、100%、97.3%。无药害,有促进出苗作用,用药剂量小,预防效果极显著,经济有效。  相似文献   

9.
马铃薯的生长发育随着生育期的变化而变化,前期以茎叶生长为主,后期则以块茎生长为主。所以,地上部性状间,以及地上部性状与地下部性状—块茎的形成有着密切的关系。地上部株高与茎叶重、叶面积之间有着极显著的正相关,相关系数分别为r=0.9359**,和r=0.8488**;茎叶重与叶面积系数之间呈极显著的正相关,r=0.9605**。株高与地下部块重之间呈显著的正相关,r=0.6843*,茎叶重与地下部块重间的关系为正相关,r=0.4285,叶面积系数与地下部块重有着微弱的正相关关系,r=0.1534。  相似文献   

10.
地理环境对大豆种子中异黄酮积累的影响趋势   总被引:14,自引:4,他引:14  
以7个异黄酮含量显著不同的大豆品种或品系分别在7个地区种植,利用HPLC技术分析所收种子中的异黄酮含量。以期获得种子中的异黄酮积累与地理环境之间的相互关系。结果显示,在7个地区中各品种异黄酮平均含量显著不同,山西最高(2492.3μg/g),湖北最低(763.4μg/g)。同一品种在不同地区其变异系数也不同,吉林3号变异系数最高(49.4%);张家口黑豆最低(33.5%)。7个大豆品种异黄酮含量与纬度和海拔高度呈正相关,与经度呈负相关,且与纬度的相关程度最高,均达到显著或极显著水平,与经度和海拔高度的相关程度相对较低。另外,各品种与各地区的平均气温和降水量呈负相关,与日照时数呈正相关,且与平均气温的相关程度最高(r=-0.879**)  相似文献   

11.
12.
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.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

14.
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   

15.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

16.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

17.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

18.
Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China.  相似文献   

19.
Evolutionary aspects of the trade-off between seed size and number in crops   总被引:1,自引:0,他引:1  
Victor O. Sadras   《Field Crops Research》2007,100(2-3):125-138
Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.

The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).

The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors.  相似文献   


20.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

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