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991.
Srinivasan Samineni Pooran M. Gaur Timothy D. Colmer L. Krishnamurthy Vincent Vadez Kadambot H. M. Siddique 《Euphytica》2011,182(1):73-86
Chickpea (Cicer arietinum L.) is known to be salt-sensitive and in many regions of the world its yields are restricted by salinity. Recent identification
of large variation in chickpea yield under salinity, if genetically controlled, offers an opportunity to develop cultivars
with improved salt tolerance. Two chickpea land races, ICC 6263 (salt sensitive) and ICC 1431 (salt tolerant), were inter-crossed
to study gene action involved in different agronomic traits under saline and control conditions. The generation mean analysis
in six populations, viz. P1, P2, F1, F2, BC1P1 and BC1P2, revealed significant gene interactions for days to flowering, days to maturity, and stem Na and K concentrations in control
and saline treatments, as well as for 100-seed weight under salinity. Seed yield, pods per plant, seeds per plant, and stem
Cl concentration were controlled by additive effects under saline conditions. Broad-sense heritability values (>0.5) for most
traits were generally higher in saline than in control conditions, whereas the narrow-sense heritability values for yield
traits, and stem Na and K concentrations, were lower in saline than control conditions. The influence of the sensitive parent
was higher on the expression of different traits; the additive and dominant genes acted in opposite directions which led to
lower heritability estimates in early generations. These results indicate that selection for yield under salinity would be
more effective in later filial generations after gene fixation. 相似文献
992.
Reciprocal differences, mostly caused by cytoplasmic effects, are frequently observed in interspecific hybrids. Previously,
we found that crosses onto Solanum demissum were much successful with the pollen of interspecific hybrids between S. tuberosum as female and S. demissum as male (TD hybrids) than the reciprocal ones (DT hybrids). To elucidate this reciprocally different crossability, we analyzed
the pollen DNA of TD and DT using methylation-sensitive amplified polymorphism (MSAP) analysis. Using 126 primer combinations,
MSAP analysis revealed 57 different bands between bulked pollen DNA samples of TD and DT. Individual examination of 16 TD
and 9 DT plants disclosed eight bands uniformly different between TD and DT. Their sequencing results revealed two pairs of
bands to be identical to each other, resulting in six distinct sequences. As expected, one band shared high homology with
chloroplast DNA, and another one with mitochondrial DNA. However, one band that was apparently different at DNA sequence level
and maternally transmitted from S. demissum, showed no homology with any known sequence. The remaining three bands were of DNA methylation level differences with no
or uncertain homology to known sequences. To our knowledge, this is the first report detecting reciprocal differences in DNA
sequence or DNA methylation other than those in cytoplasmic DNA. 相似文献
993.
Ningthoujam Sandhyarani Rajkumar Kishor Gurumayum Jitendra Sharma 《Journal of Crop Science and Biotechnology》2011,14(3):213-217
Acorus calamus is an important medicinal plant which has been used in Indian traditional medicine since time immemorial. Various bioactive
molecules, viz., acorin, α- and β-asarone, asaryldehyde, caryophylene, isoasarone, methylisoeugenol, and safrol have been isolated from this
plant. However, the use of this plant for medicinal purpose has been recently banned due to the high toxic property of β-asarone.
The triploid Acorus calamus is reported to be low in β-asarone content and thus found to be the ideal raw material for medicinal use. The present investigation
represents our finding for successful in vitro clonal propagation of the elite triploid accessions of Acorus calamus for mass propagation. In the dual-phase culture system consisting of agar-solidified Murashige and Skoog medium overlaid
by liquid fraction of the same medium, maximum multiple shoot induction was favored by supplementation of α-naphthaleneacetic
acid (0.5 mg L−1) and 6-benzylaminopurine (2.0 mg L−1). In vitro rooting of the microshoots was maximum in the medium supplemented with indolebutyric acid at 2.0 mg L−1. The well-rooted microshoots could be successfully hardened and transplanted in the field. This result can be reproduced
and is a viable protocol for successful clonal propagation of the seedless triploid Acorus calamus for conservation and sustainable development. 相似文献
994.
Mahipal S. Shekhawat Narpat S. Shekhawat Harish Kheta Ram Mahendra Phulwaria Amit Kumar Gupta 《Journal of Crop Science and Biotechnology》2011,14(2):133-137
An in vitro propagation method for female plants of Momordica dioica (Roxb.) has been established. The nodal segments were harvested and the cut ends of the explants were sealed with wax and
then surface sterilized and cultured. Bud breaking occurred on Murashige and Skoog’s (MS) agar-gelled medium + 2.0 mg L−1 6-Benzylaminopurine (BAP) + 0.1 mg L−1 Indole-3 acetic acid (IAA). The cultures were amplified by passages on MS medium supplemented with 1.0 mg L−1 BAP + 0.1 mg L−1 IAA. Further, shoot amplification (29.2 shoots per vessel) was achieved by subculturing of in vitro regenerated shoot clump on MS medium + 0.5 mg L−1 BAP + 0.1 mg L−1 IAA. The micropropagated shoots were subsequently transferred for root formation on half-strength MS medium + 2.0 mg L−1 Indole-3 butyric acid (IBA) with 89% success rate. The in vitro-regenerated shoots were also rooted ex vitro with 34% success. These plantlets were hardened in the greenhouse and transferred to the field. The established protocol
is suitable for true to type cloning of mature female plant of M. dioica. 相似文献
995.
Weixian Liu Moon Young Kim Kyujung Van Yeong-Ho Lee Hulin Li Xianhu Liu Suk-Ha Lee 《Journal of Crop Science and Biotechnology》2011,14(1):65-70
Two soybean recombinant inbred line populations, Jinpumkong 2 × SS2-2 (J × S) and Iksannamulkong × SS2-2 (I x S) showed population-specific
quantitative trait loci (QTLs) for days to flowering (DF) and days to maturity (DM) and these were closely correlated within
population. In the present study, we identified QTLs for six yield-related traits with simple sequence repeat markers, and
biological correlations between flowering traits and yield-related traits. The yield-related traits included plant height
(PH), node numbers of main stem (NNMS), pod numbers per plant (PNPP), seed numbers per pod (SNPP), 100-seed weight (SW), and
seed yield per plant (SYPP). Eighteen QTLs for six yield-related traits were detected on nine chromosomes (Chrs), containing
four QTLs for PH, two for NNMS, two for PNPP, three for SNPP, five for SW, and two for SYPP. Two highly significant QTLs for
PH and NNMS were identified on Chr 6 (LG C2) in both populations where the major flowering gene, E1, and two DF and DM QTLs were located. One other PNPP QTL was also located on this region, explaining 12.9% of phenotypic
variation. Other QTLs for yield-related traits showed population-specificity. Two significant SYPP QTLs potentially related
with QTLs for SNPP and PNPP were found on the same loci of Chrs 8 (Satt390) and 10 (Sat_108). Also, highly significant positive
phenotypic correlations (P < 0.01) were found between DF with PH, NNMS, PNPP, and SYPP in both populations, while flowering was negatively correlated
with SNPP and SW in the J × S (P < 0.05) and I × S (P < 0.01) populations. Similar results were also shown between DM and yield-related traits, except for one SW. These QTLs identified
may be useful for marker-assisted selection by soybean breeders. 相似文献
996.
Heavy doses of N fertilizers are commonly applied to green tea fields in Japan, and cause large amount of nitrate leaching
in ground water and emission of ammonia and nitrous oxide (N2O) to the atmosphere. The Denitrification and Decomposition (DNDC) model was tested against experimental data on N2O emissions from the tea field in Nishio, Aichi, Japan. There were reasonable agreements between the simulated and measured
values of N2O emissions for this site. The model was then applied for estimating the environmental impacts as affected by farm management
practices, climate change, and soil properties. The model results were assessed with respect to major indicators of agro-ecosystems
including crop yield, soil organic carbon sequestration, nitrate leaching loss, and N2O emission. The results indicated that use of compost significantly reduced nitrate leaching and N2O emissions in comparison with N fertilizer. When soil pH and texture shifted to non-acidic and coarser soil, N2O emission increased; and a change in temperature and precipitation affected N2O emission, nitrate leaching, and SOC sequestration. This study thus revealed the biogeochemistry model as a powerful tool
in addressing the complex efficacy of the alternative farm management practices in tea fields across various climate and soil
conditions. 相似文献
997.
Mi-Young Kang Catherine W. Rico Sang-Chul Lee 《Journal of Crop Science and Biotechnology》2011,14(2):111-118
The physicochemical properties of pigmented (Midorimochi, Jeokjinjubyeo, and Heukmichalbyeo) and non-pigmented (Hwayoungbyeo)
rice varieties were investigated. Starch from non-pigmented rice consisted mainly of large polyhedral granules that were more
loosely packed than those of the non-pigmented sample. Pigmented rice showed higher linoleic acid content (36–40%) and hydrolysis
rate (63–79%) but lower oleic acid content (35–39%), blue value (0.05–0.17), and viscosity values than the non-pigmented one.
Significantly higher mineral content, blue value, and pasting and viscosity values were observed in the Jeokjinjubyeo sample
compared to those of the other pigmented rice samples. The Midorimochi variety, on the other hand, exhibited the highest total
amino acid (816.82 ng mg−1) and sugar (0.15–3.35 μg g−1) contents and the lowest pasting and viscosity values. No substantial difference in the X-ray diffraction pattern was observed
among the samples. Results of this study could serve as baseline information for the quality evaluation of three pigmented
rice cultivars and provide a better understanding of their potential uses and food industry applications. 相似文献
998.
This paper introduces a combined modelling approach using a simple water budget model (THC-model) and a 3D reservoir sedimentation
model (MOHID Water) to adapt reservoir operation and visualise their effects on the sediment deposition. By this, an effective
combined sediment-water management can be identified under semi-arid conditions for dry, median and wet years. Results are
presented for the reservoirs of the Tuyamuyun Hydro-Complex (THC), which is located in the lower Amu Darya River. The determination
of the actual and usable reservoir storage volume shows that siltation will significantly adversely affect the ability of
the in-stream Channel Reservoir to regulate seasonal demand for both irrigation and municipal water supply. However, modelling
scenarios results confirm the effectiveness of adapted operation rules for the THC reservoirs and show that the operation
of large dams could be modified according to a combined sediment-water management. The experience gained during this study
emphasizes the fact that the concept of a combined reservoir management of sediments as well as water can be an efficient
measure to improve the sustainable long-term use of reservoirs and to contribute towards a safe water supply in water crisis
regions. 相似文献
999.
Anthony Winson 《Agriculture and Human Values》2008,25(4):499-511
To understand the phenomenon of the rapidly increasing prevalence of overweight and obese children and youth, it is especially
important to examine the school food environment, the role of structural factors in shaping this environment, and the resulting
nutrition and health outcomes. The paper examines research on school food environments in the US and Canada. It notes evidence
of widespread availability of poor nutrition products in both environments and delineates reasons for the situation, and examines
initiatives presently being undertaken in a number of jurisdictions in both countries to encourage healthy eating in schools.
Empirical data are presented from a pilot study of high schools in the Canadian province of Ontario. The study documents the
extent of student purchasing of nutrient-poor foods and beverages, and the structural factors internal and external to the
school that appear responsible for the availability of such products in food environments in this critical institutional sphere.
The paper also examines positive local initiatives in high schools that seek to encourage healthy eating in schools.
Anthony Winson PhD is a professor in the department of sociology and anthropology at the University of Guelph. He has written on agriculture, food and rural development, and restructuring issues related to Canada and the Third World for more than 20 years. Among his books are The Intimate Commodity: Food and the Development of the Agro-Industrial Complex in Canada (Garamond 1993) and, more recently, Contingent Work, Disrupted Lives (University of Toronto 2002, with Belinda Leach) which examines economic restructuring, the changing world of work, and the factors underlying sustainability in small manufacturing-dependent rural communities in several regions of Ontario. This book won the John Porter Book Prize of the Canadian Sociology and Anthropology Association for 2003. Dr. Winson’s current work is focused on the analysis of factors shaping the contemporary Canadian food environment and their role in producing what has been termed the “epidemic of obesity.” Particular attention is being paid to supermarkets and schools as part of broader-ranging research on the political economic context of the food environment. 相似文献
Anthony WinsonEmail: |
Anthony Winson PhD is a professor in the department of sociology and anthropology at the University of Guelph. He has written on agriculture, food and rural development, and restructuring issues related to Canada and the Third World for more than 20 years. Among his books are The Intimate Commodity: Food and the Development of the Agro-Industrial Complex in Canada (Garamond 1993) and, more recently, Contingent Work, Disrupted Lives (University of Toronto 2002, with Belinda Leach) which examines economic restructuring, the changing world of work, and the factors underlying sustainability in small manufacturing-dependent rural communities in several regions of Ontario. This book won the John Porter Book Prize of the Canadian Sociology and Anthropology Association for 2003. Dr. Winson’s current work is focused on the analysis of factors shaping the contemporary Canadian food environment and their role in producing what has been termed the “epidemic of obesity.” Particular attention is being paid to supermarkets and schools as part of broader-ranging research on the political economic context of the food environment. 相似文献
1000.
Diana Stuart 《Agriculture and Human Values》2008,25(2):177-181
I explore the role of nature in the agrifood system and how attempts to fit food production into a large-scale manufacturing
model has lead to widespread outbreaks of food borne illness. I illustrate how industrial processing of leafy greens is related
to the outbreak of E. coli 0157:H7 associated with spinach in the fall of 2006. I also use this example to show how industry attempts to create the
illusion of control while failing to address weaknesses in current processing systems. The leafy greens industry has focused
efforts on sterilizing the growing environment and adopting new technologies, while neglecting to change the concentrated
structure of processing systems. Repeated breakdowns in these systems illustrate a widening fault line between attempted and
failed control of nature in industrial food production.
相似文献
Diana StuartEmail: |