全文获取类型
收费全文 | 175篇 |
免费 | 8篇 |
国内免费 | 5篇 |
专业分类
林业 | 2篇 |
农学 | 43篇 |
基础科学 | 6篇 |
32篇 | |
综合类 | 40篇 |
农作物 | 18篇 |
水产渔业 | 1篇 |
畜牧兽医 | 6篇 |
植物保护 | 40篇 |
出版年
2023年 | 4篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 21篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 8篇 |
2009年 | 2篇 |
2008年 | 14篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 6篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1998年 | 12篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1978年 | 1篇 |
1955年 | 2篇 |
排序方式: 共有188条查询结果,搜索用时 31 毫秒
51.
白春晖 《农业机械化与电气化》2014,(6):89-90
阜蒙县是辽宁重要杂粮生产基地,而谷子已成为当地耐瘠薄、抗干旱的重要避灾作物。介绍阜蒙县耕地特点以及谷子生产现状、种植优势,分析当前谷子产业发展中存在的问题,从新品种引选、栽培技术优化、引进深加工业、健全市场营销体系等方面.提出促进阜蒙县谷子产业化发展的对策。 相似文献
52.
In light of growing concerns about obesity, Winson (2004, Agriculture and Human Values 21(4): 299–312) calls for more research into the supermarket foodscape as a point of connection between consumers and food
choice. In this study, we systematically examine the marketing of ready-to-eat breakfast cereals to children in Toronto, Ontario
supermarkets. The supermarket cereal aisle is a relatively unstudied visual collage of competing brands, colors, spokes-characters,
and incentives aimed at influencing consumer choice. We found that breakfast cereal products with higher-than-average levels
of sugar, refined grains, and trans-fats are more likely to feature child-oriented marketing in the form of spokes-characters,
themed cereal shapes/colors, and child incentives on cereal boxes. These forms of visual communication are consistent with
a “health exploitive” pattern of targeted marketing to children in the supermarket setting. Only one aspect of visual communication
is consistent with a “health protective” pattern of marketing to children—cereals shelved within reach of children aged 4–8
had less sugar per serving and were less likely to contain trans-fats than less reachable products. We discuss the implications
of our findings for the measurement and regulation of marketing to children in North American supermarkets.
Brent Berry who has a PhD from the University of Michigan, is an Assistant Professor of Sociology at the University of Toronto in Ontario, Canada. His most recent research has sought to untangle the casual processes underlying socioeconomic disparities in health over the lifecourse. Brent has also developed innovative visual approaches for systematically studying interracial friendships, homelessness, and marketing in supermarkets. Brent has also published work on race and ethnic relations, residential segregation, social theory, and family intergenerational support. His work has been published in Demography, Health, Evaluation Review, Ethnic and Racial Studies, the Journal of Family Issues, and the American Journal of Economics and Sociology. Taralyn McMullen is a doctoral candidate in Sociology at the University of Toronto. Taralyn is interested in the sociology of health and illness, with emphasis on issues of food insecurity. In addition to her collaborative work with Brent Berry, Taralyn has completed a research project examining the link between food insecurity, obesity, and gender discrimination in Canada. 相似文献
Brent BerryEmail: |
Brent Berry who has a PhD from the University of Michigan, is an Assistant Professor of Sociology at the University of Toronto in Ontario, Canada. His most recent research has sought to untangle the casual processes underlying socioeconomic disparities in health over the lifecourse. Brent has also developed innovative visual approaches for systematically studying interracial friendships, homelessness, and marketing in supermarkets. Brent has also published work on race and ethnic relations, residential segregation, social theory, and family intergenerational support. His work has been published in Demography, Health, Evaluation Review, Ethnic and Racial Studies, the Journal of Family Issues, and the American Journal of Economics and Sociology. Taralyn McMullen is a doctoral candidate in Sociology at the University of Toronto. Taralyn is interested in the sociology of health and illness, with emphasis on issues of food insecurity. In addition to her collaborative work with Brent Berry, Taralyn has completed a research project examining the link between food insecurity, obesity, and gender discrimination in Canada. 相似文献
53.
Practical breeding for durable resistance to rust diseases in self-pollinating cereals 总被引:3,自引:0,他引:3
R. Johnson 《Euphytica》1978,27(2):529-540
Summary The rust pathogens of cereals exist as populations of races that differ in their ability to attack various varieties. Varieties that are resistant when first released often become susceptible later due to the spread of previously undetected races but the time taken for this to occur in very variable. It often occurs so rapidly as to curtail the commercial use of otherwise satisfactory varieties.Some varieties, however, are widely grown for many years and remain adequately resistant to the prevalent rust diseases. They may aptly be described as having durable resistance. This durable or long-lasting resistance can be detected without any assumptions about, or detailed knowledge of, whether durability depends on any particular mechanisms of resistance, on various degrees of racespecificity or on many or few genes. Cappelle-Desprez is given as an example of a wheat variety with durable resistance to yellow rust.The most powerful test for the detection of durable resistance occurs when a variety is widely grown commercially for several years. A much weaker test is obtained by growing varieties in small disease nursery plots even when the test is repeated for several years. Usually, resistance which is durable is also partial or incomplete. Often, however, partial resistance of wheat to yellow rust has not been durable. Thus the observation that resistance is partial is not, of itself, a satisfactory criterion for the detection of durable resistance.It is suggested that the most obvious sources of durable resistance for use in breeding programmes are varieties which have been widely grown and have displayed this character. The transfer of such resistance during breeding may be achieved if the creation or incorporation of higher levels of resistance that have not been tested for durability is avoided. It should then be possible to derive resistance from the durably. resistant parent. Methods of achieving this are discussed. 相似文献
54.
C. M. Josephides 《Euphytica》1992,65(1):1-8
Summary Yield data obtained from a comparative small grain cereals trial, grown for five consecutive growing seasons at a total of 23 environments in Cyprus, were subjected to regression analysis. Within each environment, yield trials consisted of a standard set of three cultivars or elite lines of barley, triticale, durum and bread wheat. The regression coefficient (b) of crop mean on the environmental index (I) and the mean square deviation from regression (sd2) were calculated for each crop. Each crop tended to have its own characteristic value of sd2 and its magnitude was an excellent indicator of specific crop-environment interaction. The causes of large sd2, for two of the four crops, were the susceptibilith of barley to lodging, when favourable conditions were encountered at high yielding environments, and triticale dependence on late season precipitation. Durum wheat and triticale had an average response to different yielding environments (b>1.19) and both were significantly different from those of bread wheat (1.08) and barley (0.54). Hence, barley, bread and durum wheat are specifically adapted to low, average and high yielding Mediterranean environments, respectively. The cultivation of triticale at the expence of durum wheat is not feasible. Furthermore, interactions between crops and environments demonstrated by the regression parameters, should constitute the basis for decision making, regarding crop adaptation in a region. The average yield in all environments should not be considered as a proper criterion for adaptation. In this study, triticale had a similar mean grain yield (3,842 kg/ha) to that of bread wheat, but was significantly higher yielding than barley or durum wheat (5 and 7%, respectively). 相似文献
55.
Genetic variation in specific root length in Scandinavian wheat and barley accessions 总被引:1,自引:0,他引:1
Specific root length (SRL, m root g–1 root dry matter) was studied in a broad selection of old and current accessions of spring wheat and barley from Norway and Sweden, at sub-optimal phosphorus conditions in nutrient solution and soil. The results indicated that genotype did not have a significant effect on SRL. A close relationship between root length (RL) and root weight (RW) was found, and more than 70% of the variation in root length was explained by root weight of representative and homogenous root samples. In nutrient solution, the relationship between RL and RW was described by the regression equations RL = 0.32 RW—0.19 (R
2= 0.74) for wheat and RL = 0.20RW + 0.73 (R
2= 0.56) for barley. In the soil experiment, the relationships between RL and RW were described by the equations RL = 0.15RW + 0.95 (R
2= 0.67) for barley and RL = 0.16 RW + 0.50 (R
2= 0.77) for wheat. Hence, in screenings of a large number of cereal genotypes, the root length may be estimated with good accuracy by records of root weight and an appropriate regression equation. 相似文献
56.
M. Hegedüs Birthe Pedersen Dr. B. O. Eggum 《Plant foods for human nutrition (Dordrecht, Netherlands)》1985,35(2):175-180
Rye, wheat, barley, rice, maize and sorghum were milled into more or less refined fractions, and the content of thiamin, riboflavin, vitamin B6, folate, biotin, niacin and tryptophan were determined. Differences in vitamin content between the different cereal grains were rather small. Refining resulted in marked losses of all vitamins studied. On average, 70%–80% of the vitamins were lost during the milling process. The lowest vitamin content was found in highly refined rice, containing only about 5% of the folate and 10% of the niacin present in brown rice. Maize had a low content of tryptophan, and the concentration was greatly reduced by degerming. For the other cereal grains, milling had only a slight effect on tryptophan concentrations. 相似文献
57.
邵万宽 《农产品加工.学刊》2013,(3):77-80
杂粮及根茎蔬果原料的食品制作是我国食品生产的重要组成部分。近年来,随着国民经济的发展和人们营养需求的提升,主食杂粮与根茎蔬果类食品颇受城乡居民的青睐,在餐厅、超市都出现了旺销局面。对于生产者和研发者来说,无论是品种的开发、口味的变化、技艺的创新等,都需要不断地探索与研究,以加快杂粮等食品的发展进程,去适应人们不断增长的物质需要。 相似文献
58.
Caterina Morcia Elisa Rattotti A. Michele Stanca Giorgio Tumino Vittorio Rossi Stefano Ravaglia Christoph U. Germeier Matthias Herrmann Ivana Polisenska Valeria Terzi 《Journal of Cereal Science》2013
Risks associated with mycotoxin contamination of cereals, that are included in the ten major staple foods and greatly contribute to the dietary energy intake, are of worldwide relevance. In small grain cereals, mycotoxins are produced by fungi such as Aspergillus, Penicillium, Alternaria and Fusarium that colonize the plant in the field and can grow during the post-harvest period, producing several classes of mycotoxins. The identification of mycotoxigenic fungal species and strains is essential for developing effective strategies for control. For this purpose, genetic traceability has proved to be a valuable tool that can be applied along the whole production chain, starting in the field for early diagnosis of FHB (Fusarium Head Blight) disease to the final processing steps, such as malting or pasta making. In this paper, DNA-based analytical tools that are currently available for the identification and quantification of mycotoxigenic fungal species and strains are reviewed, with particular emphasis on Fusarium, and their possible applications in mycotoxin control in small grain cereal chains are discussed. 相似文献
59.
John A. Winder 《国际虫害防治杂志》2013,59(4):449-466
Abstract The sphingid moth Erinnyis ello L. is an important pest of cassava and the most serious pest of the rubber tree in the New World; E. alope Drury is sometimes a serious pest of papaya. Information on the known food plants, life cycle, behaviour, natural enemies, seasonal abundance and present methods of control of these two lepidopterous pests is reviewed. The perspectives for improved control of E. ello with special reference to rubber plantations in Brazil, through the manipulation of natural enemies, a more rational use of insecticides and the adoption of certain cultural methods, are discussed. 相似文献
60.
青稞在西藏长期以来的产业发展中,基本以糌粑、青稞米等初级产品为主,为开拓更多的青稞加工方式,丰富产品类别,对青稞粉进行挤压膨化及工艺的优化,并结合当地杂粮鸡爪谷等,通过挤压膨化提升青稞的口感及相关产品的营养价值。青稞杂粮粉挤压膨化后,对不同膨化参数组合的青稞杂粮粉的吸水性、水溶性、堆积密度、沉降性、分散性、润湿性等指标进行了测定,发现膨化参数组合之间没有表现出明显的速溶差异特性。青稞杂粮膨化率的大小不跟速溶性指标呈正比关系。根据膨化效果最佳膨化工艺参数为物料水分含量为12%,Ⅲ区温度170℃,主轴转速20 Hz,喂料速度8 Hz;从速溶粉的生产工艺来看,最佳工艺为物料水分含量为16%,Ⅲ区温度170℃,主轴转速23 Hz,喂料速度8 Hz。 相似文献