全文获取类型
收费全文 | 322篇 |
免费 | 34篇 |
专业分类
林业 | 20篇 |
农学 | 9篇 |
基础科学 | 2篇 |
67篇 | |
综合类 | 7篇 |
农作物 | 26篇 |
水产渔业 | 57篇 |
畜牧兽医 | 139篇 |
园艺 | 9篇 |
植物保护 | 20篇 |
出版年
2023年 | 6篇 |
2022年 | 5篇 |
2021年 | 37篇 |
2020年 | 23篇 |
2019年 | 34篇 |
2018年 | 29篇 |
2017年 | 16篇 |
2016年 | 20篇 |
2015年 | 17篇 |
2014年 | 17篇 |
2013年 | 13篇 |
2012年 | 27篇 |
2011年 | 39篇 |
2010年 | 13篇 |
2009年 | 11篇 |
2008年 | 13篇 |
2007年 | 4篇 |
2006年 | 7篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1997年 | 2篇 |
1989年 | 1篇 |
排序方式: 共有356条查询结果,搜索用时 15 毫秒
111.
112.
Facundo Tabbita Silvina Lewis Juan P. Vouilloz María A. Ortega Mariana Kade Pablo E. Abbate Atilio J. Barneix 《Plant Breeding》2013,132(1):48-52
Wheat grain protein content (GPC) is important for human nutrition and has a strong influence on the quality of pasta and bread. The objective of this study was to analyse the introduction of the Gpc‐B1 allele into two Argentinean bread wheat cultivars. Near‐isogenic lines were developed in ‘ProINTA Oasis’ and ‘ProINTA Granar’ using marker‐assisted selection. Gpc‐B1 lines showed a significant (P = 0.01) increase in GPC and a significant (P = 0.001) decrease in grain weight in comparison with control lines without Gpc‐B1. Differences in yield were not significant (P = 0.49) between lines. Gpc‐B1 lines significantly reduced (P = 0.02) straw nitrogen concentration at maturity and significantly increased (P = 0.02) the nitrogen harvest index. When data were analysed by genotype and environment, differences in some analysed parameters were found, indicating that Gpc‐B1 expression may be affected by different genetic backgrounds and environmental conditions. These results suggest that the introgression of the Gpc‐B1 allele into Argentinean wheat germplasm could be a valuable resource for improving GPC with no detrimental effect on grain yield. 相似文献
113.
Mariana Yante B. Pereira 《Asia Pacific viewpoint》2021,62(1):116-130
The article aims at discussing the rise of the green bonds in the context of the multilateral development banks, by problematizing their threats and potentialities to be an alternative to the existing financing system within the sustainable development agenda. It scrutinises the development rhetoric behind the emergence of multilateral development banks in the Global South, specifically in the Asian context, and attempts to foster alternatives to the Bretton Woods institutions. The two largest initiatives in that sense – the New Development Bank and the Asian Infrastructure Investment Bank – started in Asia and also target countries in the region, giving the growing influence of China and the enhancement of interregional cooperation through the BRICS countries, currently led by China, India and Russia. The paper argues that there is limited scope for the promised innovations in both project assessment and the role of private capital, given the prioritisation of infrastructure as the premise to achieving the right to development among emerging and least‐developed economies. The research departed from the quantitative and qualitative analysis of the projects funded by the New Development Bank and the Asian Infrastructure Investment Bank, from their inception until 2018, considering the approach that such institutions have taken to the social and environmental standards from their normative framework. 相似文献
114.
This study has compared the phytolith production and soil phytolith assemblages of two native grass communities typical in Argentina, namely the monospecific Paspalum quadrifarium community or “pajonal”, and the Stipa-Piptochaetium community or “flechillar”. Five sites – three of which had been unmanaged while other two had been submitted to fire and fire-grazing management activities – were selected for study. The results show that in these sites a) phytolith production of the plant communities differed due to their diverse floristic composition, b) it was possible to define the type of management or the type of community based on soil phytolith assemblages, c) there were differences between plant communities and soil phytolith assemblages. These results suggest that modern phytolith assemblages are composed not only of local and present vegetation but also of extralocal/regional and probably past vegetation. Hypotheses about the probable processes involved in phytolith incorporation to soil have emerged during the investigation. 相似文献
115.
116.
117.
118.
Décio Oscar Cardoso Ferreto Juliano do Prado Rodrigues Mariana Alves Ibarr Cassio Strassburger de Oliveira Renan Costa Beber Vieira Mirla Andrade Weber 《Journal of plant nutrition》2016,39(3):399-409
Boron (B) requirement and its interaction with liming for eucalyptus plantations in sandy soils of Brazilian Pampa are poorly understood. Aiming to diminish this gap, seedlings of Eucalyptus urograndis were grown in pots with Arenosol fertilized with B at rates 0.0, 1.0, 2.5, 5.0 and 10.0 mg B dm?3, with and without liming. Results of shoot and root dry matter and stem diameter did not evidence the necessity of B fertilization. With the exception of the 1.0 mg B dm?3+lime, all other B-fertilized treatments promoted visual symptoms of toxicity, which were partially mitigated by liming. Liming exacerbated the B loss by leaching, but after five months, limed soils had higher content of available B and their plants had higher B concentration in shoots and roots. For our conditions, application of ≥2.5 mg B dm?3 can cause serious toxic injuries to plants and enlarge dramatically the B losses leaching. 相似文献
119.
Mariana Laura Feldman Adriana Balbina Andreu Samanta Korgan María Candela Lobato Marcelo Huarte Linda Lee Walling Gustavo Raúl Daleo 《Plant Breeding》2014,133(2):275-280
Potato leaves infected with Phytophthora infestans produced a serine protease inhibitor (PLPKI) with specificity for microbial proteases. Sequencing of the first twenty residues at the NH2‐terminus of the mature PLPKI polypeptide demonstrated that PLPKI is a novel member of the potato protease inhibitor I family. PLPKI inhibited the activity of extracellular proteases produced by two pathogens of potato, P. infestans and Rhizoctonia solani, but was inactive against proteases secreted into the culture media by the binucleate Rhizoctonia N2, a non‐pathogenic fungus for potato. Western blot analysis showed a positive correlation between the levels of PLPKI and the degree of horizontal resistance, showing its highest accumulation in clone OKA 5632.11, which has been described as highly resistant. This correlation, together with the ability of PLPKI to completely abolish the secreted serine protease activity of P. infestans, suggests that PLPKI may have an active role in protecting potato plants from this pathogenic oomycete and that it could be used as a suitable biochemical marker to help breeders in the selection of cultivars with high degree of horizontal resistance. 相似文献
120.
Mauricio Quesada G. Arturo Sanchez-Azofeifa Mariana Alvarez-Añorve Kathryn E. Stoner Luis Avila-Cabadilla Julio Calvo-Alvarado Alicia Castillo Mario M. Espírito-Santo Marcilio Fagundes Geraldo W. Fernandes John Gamon Martha Lopezaraiza-Mikel Deborah Lawrence Leonor Patricia Cerdeira Morellato Jennifer S. Powers Frederico de S. Neves Victor Rosas-Guerrero Roberto Sayago Gumersindo Sanchez-Montoya 《Forest Ecology and Management》2009
Understanding tropical forest succession is critical for the development of tropical forest conservation strategies worldwide, given that tropical secondary forests can be considered the forests of the future. Tropical dry forests (TDF) are among the most threatened tropical ecosystems, there are more secondary forests and forest restoration efforts that require a better understanding of successional processes. The main goal of this synthesis for this special issue on the ecology and management of tropical dry forests in the Americas is to present a summarized review of the current knowledge of the ecology and management implications associated to TDF succession. We explore specific issues associated to tropical dry forest succession with emphasis on the use of chronosequences, plant diversity and composition, plant phenology and remote sensing, pollination, and animal–plant interactions; all under the integrating umbrella of ecosystem succession. We also emphasize the need to conduct socio-ecological research to understand changes in land-use history and its effects on succession and forest regeneration of TDF. We close this paper with some thoughts and ideas associated with the strong need for an integrating dimension not considered until today: the role of cyberinfrastructure and eco-informatics as a tool to support sound conservation, management and understanding of TDF in the Americas. 相似文献