全文获取类型
收费全文 | 165篇 |
免费 | 18篇 |
专业分类
林业 | 40篇 |
农学 | 3篇 |
32篇 | |
综合类 | 19篇 |
农作物 | 7篇 |
水产渔业 | 8篇 |
畜牧兽医 | 56篇 |
园艺 | 4篇 |
植物保护 | 14篇 |
出版年
2024年 | 1篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 11篇 |
2011年 | 23篇 |
2010年 | 9篇 |
2009年 | 7篇 |
2008年 | 11篇 |
2007年 | 9篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 10篇 |
2003年 | 8篇 |
2002年 | 7篇 |
2001年 | 2篇 |
1999年 | 2篇 |
1994年 | 1篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有183条查询结果,搜索用时 0 毫秒
181.
Effectiveness of native West African arbuscular mycorrhizal fungi in protecting vegetable crops against root-knot nematodes 总被引:1,自引:0,他引:1
Antoine Affokpon Louis Lawouin Colette Tossou Rufin Dossou Agbèdè Jozef Coosemans 《Biology and Fertility of Soils》2011,47(2):207-217
Twenty strains of arbuscular mycorrhizal fungi (AMF), native to West Africa, and three commercial AMF, were evaluated for
their protective effect against root-knot nematodes, Meloidogyne spp., in pots and field experiments in Benin. In pots, these strains were assessed in sterilized soil following inoculation
of nematodes and in non-sterilized soil naturally infested with nematodes using tomato. The four strains showing greatest
potential in suppressing nematode development were further assessed in the field with a relatively high natural infestation
level of nematodes (155 per 100 cm3 soil) over a tomato–carrot double cropping. In the pot experiments, most native strains provided significant suppression
of nematode multiplication and root galling, but in most cases the level of nematode control depends on either sterilized
or non-sterilized soils. In the field experiments, application of AMF mostly resulted in significant suppression of nematode
multiplication and root galling damage on both crops indicating that the AMF persists and remains protective against root-knot
nematodes over two crop cycles. Field application of AMF increased tomato yields by 26% and carrot yields by over 300% compared
with the non-AMF control treatments. This study demonstrates for the first time, the protective effect of indigenous West
African AMF against root-knot nematodes on vegetables. The potential benefits of developing non-pesticide AMF-based pest management
options for the intensive urban vegetable systems are evident. 相似文献
182.
Naisheng BaiKan He Marc RollerChing-Shu Lai Xi ShaoMin-Hsiung Pan Antoine BilyChi-Tang Ho 《Fitoterapia》2011,82(2):168-172
Two new 5-O-glucosylflavones, 5-O-β-d-glucopyranosyl cirsimaritin (1) and 5, 4′-O-β-d-diglucopyranosyl cirsimaritin (2), four known flavonoids, cirsimarin (3), cirsimaritin (4), salvigenin (5), 4′, 5-dihydroxy-7-methoxyflavone (6), and a norisoprenoid, vomifoliol (7), have been isolated from the aerial parts of Microtea debilis. All isolates were tested for cytotoxicity in human cancer cell lines (Hep G2, COLO 205, and HL-60) and anti-inflammatory activities in LPS-treated RAW264.7 macrophages. Compound 6 was found to be a potent inhibitor to nitrite production in macrophages. Compounds 2, 4, 6, and 7 showed moderate anti-proliferative activity against COLO-205 cells with IC50 values of 7.1, 13.1, 6.1, and 6.8 μM, respectively. 相似文献
183.
Laurent Larrieu Alain Cabanettes Antoine Brin Christophe Bouget Marc Deconchat 《European Journal of Forest Research》2014,133(2):355-367
Recent studies have highlighted the key role of tree microhabitats in forest habitat complexity and have suggested using them as surrogates for local taxonomic biodiversity. However, few practical guidelines have been published to help foresters in managing microhabitats at the stand scale. This paper provides scientific background information to help to develop such guidelines. We surveyed trees in nine long-unmanaged beech–fir forests to model tree microhabitat occurrence and diversity at the tree level. Data were upscaled to a size range of tree cluster, i.e., at the tree population scale, by aggregating observed values of microhabitat occurrence. Accumulation curves were used to estimate the minimum number of trees required to make all the microhabitat types available. Two managed forests were then studied to quantify management effects on microhabitats. Diameter at breast height (dbh) and tree species, respectively, explained 16 and 10 % of the variations in the number of microhabitat-bearing trees, and 21 and 10 % for the number of microhabitat types. Beech trees and firs with a dbh of less than dbh 50 and 65 cm, respectively, did not ensure the provision of all microhabitat types. At least 20 ha of unmanaged forest were necessary to conserve all the microhabitat types. Current management practices have reduced the number of microhabitat-bearing beeches both by reducing the number of very large trees (dbh > 67.5 cm) and by tree selection within mid-size diameters. For fir, only the logging of very large trees (dbh > 62.5 cm) negatively affected microhabitats. These figures may inspire guidelines for conservation-friendly forestry. 相似文献