首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   48篇
  免费   2篇
林业   1篇
农学   3篇
基础科学   3篇
  10篇
综合类   6篇
农作物   4篇
水产渔业   3篇
畜牧兽医   13篇
园艺   3篇
植物保护   4篇
  2023年   2篇
  2022年   5篇
  2021年   4篇
  2020年   3篇
  2019年   5篇
  2018年   5篇
  2017年   1篇
  2016年   2篇
  2014年   1篇
  2013年   5篇
  2012年   2篇
  2011年   3篇
  2010年   1篇
  2009年   2篇
  2008年   2篇
  2007年   2篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
排序方式: 共有50条查询结果,搜索用时 15 毫秒
1.
2.
The present study assessed the effect of arbuscular mycorrhizal fungi (AMF) on broomrape (Orobanche aegyptiaca Pers.) control to determine its effects on tomato (Lycopersicon esculentum L.) growth indices. This experiment was carried out using a randomized complete block design with four replications. The treatments included three strains of AMF (Glomus mosseae, Glomus intraradices and Glomuse hoe ) at three levels (100, 200 and 300 kg ha?1). The control treatments (without mycorrhiza) were with and without broomrape (weed infest and weed free). The results showed that the use of G. intraradices and G. mosseae decreased broomrape seed germination, the number of nodules and the dry weight of the broomrape and increased root area and dry weight of the tomato plant when compared to G. hoe and the control treatments without broomrape. The tomato yield in G. intraradices 300 kg ha?1 treatment increased by 10 and 205% than weed free and weed infest treatments, respectively. Finally, G. intraradices and G. mosseae at, respectively, 200 and 300 kg ha?1 are recommended for land under tomato cultivation that has been contaminated with broomrape.  相似文献   
3.
18 soybean genotypes were examined to investigate the relationships between some principal attributions of morphology with seed yield per soybean, by Random Complete Block Design (RCBD) study. This study was also carried out three replicates to gain reliable results. The results of variance analysis indicated that, there were significance differences among all soybean genotypes. Moreover, the results of correlated analysis revealed that biological yield (0.96), harvest index (0.92), and number of branches (0.92) had the uttermost correlation with seed yield. To data factor analysis, four independent variables justified 99 percent of all data. The first variable, seed yield, justified 96 percent of entire variance. Multiple-Regression Model with method Analytical Regression Model (step-by-step) was utilized to examine soybean seed yield. This model proved that biological yield, thousand seed weight, and harvest index entered into model respectively and justified 98.85 percent of variation of seed yield. Correlated coefficients of considered attributions were equal to 0.96, 0.78, and 0.92, respectively. All of these indexes had significant at 1% in statistical process. Therefore, these traits can be notability used in soybean breeding programs. Also, accordance to cluster analysis, the sample was divided into three groups.  相似文献   
4.
Journal of Plant Diseases and Protection - Severe fruit rot symptoms were observed on tomato crop (Lycopersicon esculentum) located in Hamedan province of Iran, in spring 2014. Affected fruits...  相似文献   
5.
Bio-drainage can be considered as an important part of sustainable irrigation water management. Bio-drainage has potential for managing shallow water conditions in arid and semiarid areas especially when traditional subsurface drains are not available. Bio-drainage theory does not go back too far. The relationship between soil characteristics, water management regimes, and climatic conditions is not yet well defined. This study attempted to use a mathematical model (SAHYSMOD) to evaluate factors affecting design and operation of a bio-drainage system and study its sensitivity to different variables. The study showed that the major constraint of bio-drainage is salt accumulation in tree plantation strips in arid and semiarid regions. Maximum soil water salinity which can be controlled by bio-drainage is around 3 dS m?1 in rather medium run and sustainability may only be achieved where a salt removal mechanism is considered. The study also showed that the effectiveness of the system is higher where the neighboring strips are narrower. It also showed that bio-drainage is very sensitive to the amount of applied water. While the barrier depth does not have an important effect on water table draw down, it does have a great influence on lowering the salinization rate of tree plantation strips. The application of bio-drainage could be economically controversial since in humid areas water is sufficient for agricultural crops, allocating parts of the expensive land to mostly non-fruit trees may not be feasible, while in arid and semiarid regions there is usually enough cheap land to grow trees.  相似文献   
6.
During our screening of plant materials to find new natural fragrance and flavor ingredients, we discovered two series of 3-sulfanylalkyl alkanoates in a peel extract of fruits of wild-growing Poncirus trifoliata (L.) Raf. (Rutaceae), a species closely related to Citrus. The two series belong to alkanoates of 3-methyl-3-sulfanylbutan-1-ol and 3-sulfanylhexan-1-ol, respectively, and thus are members of a family of natural molecules having in common a 1,3-positioned O,S moiety. The alkanoate residues comprise all even-numbered saturated fatty acids from C2 (acetate) to C18 (octadecanoate). Among the 20 sulfur-containing compounds identified, 14 are described for the first time as naturally occurring in a botanical species. Several cysteine-S-conjugates were synthesized as hypothetical precursors of the new volatile sulfur-containing constituents, where after S-(3-hydroxy-1,1-dimethylpropyl)-L-cysteine, S-[3-(acetyloxy)-1,1-dimethylpropyl]-L-cysteine, and S-[1-(2-hydroxyethyl)butyl]-L-cysteine were identified in the fruit peel. No cysteine-S-conjugates were detected in the fruit juice.  相似文献   
7.
8.
9.
尿是人类和脊椎动物为了新陈代谢的需要,经由泌尿系统及尿路排出体外的液体排泄物。近年来,骆驼尿液因具有广泛的医疗作用而引起广泛关注。在中东地区,其主要用于对疾病的辅助治疗,包括发烧、感冒甚至癌症。研究表明,骆驼尿液中含有一些独特的生物化学成分,如刀豆氨酸可在不同肿瘤中表现出细胞毒性和抗肿瘤活性。且研究证实骆驼尿液具有抗菌、保肝、抗肿瘤和抗血小板活性等重要作用,极具研究价值。文章主要介绍了骆驼尿液中的有效生物化学成分,并对骆驼尿液在各种疾病中的医药作用进行详细阐述,为今后对骆驼尿液的进一步研究提供理论依据。  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号