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121.
Pearl millet (Pennisetum glaucum) is cultivated across a wide range of environments ranging from extremely stressful to favourable. The objective of this research was to compare methods to identify productive cultivars for stress and non-stress conditions. Thirty pearl millet cultivars were evaluated at 22 locations that were grouped as stress, non-stress, or intermediate environments. Five selection indices viz., arithmetic mean (AM), geometric mean (GM), AM (standard units), stress susceptibility index (S) and drought response index (DRI) were calculated for each genotype to determine correlation between selection indices and yield under stress (YS), non-stress (YNS), and average conditions (YAV). Both cultivars and locations were significant sources of variation. Phenology of cultivars had different influence on yielding ability in contrasting environments. While earliness was advantageous for stress conditions, cultivars with longer duration tended to yield more under non-stress conditions. YS was only moderately determined by YNS. Both AM and GM were suitable indices for selection of cultivars that would perform well across stress, non-stress, and intermediate environments. Stress susceptibility index (S) was negatively correlated with YS (r=−0.62**) but should only be used as a selection criterion in combination with yield under stress (YS) to identify cultivars adapted to stress environments. DRI was positively correlated with YS but had no association with YNS. Results indicated that DRI might be useful for identifying cultivars with high performance under stress particularly when days to flower differ considerably among test entries. 相似文献
122.
K. Joseph John R. Khedasana V. A. Muhammed Nissar Sheen Scariah Shrikant Sutar S. R. Rao M. Abdul Nizar M. Latha S. R. Yadav K. V. Bhat 《Genetic Resources and Crop Evolution》2014,61(2):345-355
Cucumis setosus Cogn. is a rare, endemic, wild gathered or semi-domesticated vegetable restricted to Maharashtra state and border districts of adjoining states in India. Herbarium and literature survey shows that it is poorly collected and inadequately studied. Morphological characters, basic chromosome number and crossability barriers indicate that Cucumis setosus is a valid species, distinct from C. sativus and endemic to western India. Its morphology, basic cytology, crossability relationship with other Cucumis species, taxonomy, distribution, ecology, conservation, economic importance and viability under cultivation are discussed. Besides, a key to distinguish it from C. sativus var. hardwickii (wild and feral form of C. sativus) and other species having sympatric distribution in the area is also presented. Absence of bitter principle in the fruits makes it a potential germplasm for melon and cucumber improvement as well as direct domestication as a future crop. 相似文献
123.
Hosamani M Yadav S Kallesh DJ Mondal B Bhanuprakash V Singh RK 《Zoonoses and public health》2007,54(5):204-208
Isolation and characterization of an orf virus has been described here. The virus was isolated from an outbreak of 'scabby mouth' in goats in Northern India. Viral morphology from the scab biopsy revealed typical ovoid-shaped particles characteristic of Parapoxvirus. Virus was isolated from sonicated scab suspension and characterized by restriction enzyme (RE) analysis and sequencing of full-length GM-CSF- and interleukin-2 inhibitory factor (GIF) gene. RE pattern of the virus did not show close resemblance to most of the orf viruses published earlier. However, it showed high sequence identity and closer phylogenetic relationship with previously published ORFV-SA00 strain, as evident from the nucleotide and deduced amino acid sequence of GIF gene. 相似文献
124.
R. K. Kapila R. S. Yadav P. Plaha K. N. Rai O. P. Yadav C. T. Hash C. J. Howarth 《Plant Breeding》2008,127(1):33-37
Genetic diversity among 70 maintainers and two pollinators of sub-Saharan and Indian origin was studied for simple sequence repeat (SSR) loci using 34 primer pairs. A total of 213 alleles were detected with an average of 6.26 alleles per locus. Polymorphic information content (PIC) ranged from 0.05 to 0.96 with a mean of 0.58 for the SSR loci. Mean PIC across the linkage groups and number of alleles in dinucleotide motifs varied significantly. The lowest PIC (0.239) for linkage group 6 indicated comparatively conserved nature of this linkage group. Genetic similarity estimates ranged from 0.05 to 0.73 with an average value of 0.29. This indicated sufficient diversity among the maintainer and pollinator lines. The 72 lines fell in five clusters, and the clustering pattern corroborated with their pedigree and characteristic traits. Pollinator ICMR 356 was more diverse from the maintainer lines analysed, and can be a potential parent for pearl millet hybrid development. 相似文献
125.
Madhav P. Yadav Marshall L. Fishman Hoa K. Chau David B. Johnston Kevin B. Hicks 《Cereal Chemistry》2007,84(2):175-180
The molecular characteristics of two purified arabinoxylan fractions derived from corn kernels, corn fiber gum-1 and -2 (CFG-1 and -2), have been studied and correlated with emulsifying properties. CFG-1 and -2 fractions were isolated from different corn fiber sources by 1) a sequential alkaline extraction and H2O2 bleaching to produce CFG-1; and 2) additional H2O2 treatment of the alkali-extracted residue at pH 11.5, yielding CFG-2. Multiangle laser light-scattering and online viscosity were used to measure the molar mass, polydispersity, structure compactness, and intrinsic viscosity of the generated CFG fractions. Emulsification properties in an oil-in-water emulsion system with 10:1 oil-to-gum ratio was investigated by measuring turbidity of an aliquot from the bottom of the diluted emulsion over 10 days. The isolated CFG-2 from each fiber source was higher in weight-average molar mass (Mw) polydispersity) (Mw/Mn) and structure compactness, and also lower in solution weight-average intrinsic viscosity (ηw) than the corresponding CFG-1. Average Mw and ηw values were 244–491 kDa and 1.35–1.84 dL/g, respectively. The emulsion stabilizing capacity of CFG-2 from each fiber source was superior to the corresponding CFG-1. 相似文献
126.
This study quantified the magnitude of heterosis in pearl millet (Pennisetum glaucum) topcross hybrids produced by crossing 16 diverse landraces and three high yielding open-pollinating varieties on two homozygous
male-sterile lines. Hybrids and pollinators were grown in 12 year ×;location combinations in India that were grouped into
three zones. Genetic components of variance quantifying the differences among these hybrids were estimated. The hybrids showed
a conspicuous heterosis for grain yield, earliness and biomass yield but not for straw yield. The level and direction of heterosis
for time to flowering depended strongly on the earliness of the male-sterile line. In the terminal drought stress zone hybrids
made on the early maturing male-sterile line 843A had the highest level of heterosis for grain yield (88%). This was partly
due to escape from terminal stress. In the other two zones the heterosis for grain yield was on average 30%. Heterosis for
biomass yield and biomass yield per day was on average also positive in all three zones. For all traits, except time to flowering
and biomass yield per day, pollinator effects were the only significant source of variation. Differences between hybrids were
mostly caused by additive genetic effects. Significant amount of heterosis observed in landrace-based topcross hybrids for
grain yield and other productivity-related traits suggested that substantial improvement in pearl millet productivity in and
environments can be obtained by topcrossing locally adapted landraces on suitable male-sterile lines.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
127.
Modelling surplus canal water releases for artificial recharge of groundwater through surface drainage systems 总被引:1,自引:0,他引:1
Intensive agriculture in various countries has resulted in over-exploitation of groundwater resources leading to a decline
in the water table. Artificial groundwater recharge offers a good method of preventing the water table from declining further.
The Indo-Gangetic plain is currently facing the problem of a declining water table. The network of surface drains constructed
to control previous waterlogging could now be used for recharging groundwater with surplus canal water during the low irrigation
requirement period, as most of the drains cut across the irrigation canals. Therefore, a model was developed to determine
the optimum discharge to be released at the head of each drain under natural flow conditions and with interruption in the
flow by providing check structures across the drains at suitable intervals. In the proposed method, water is released in such
a way that outflow becomes zero at the outfall of the drain. The results obtained reveal that the strategy developed could
be adopted for recharging the declining water table through surface drainage systems.
Received: 3 February 1999 相似文献
128.
A water balance model applicable to intermittent irrigation practice in rice fields was developed. The model inputs consist
of climatic data and soil parameters. The model is formulated to simulate various processes such as evapotranspiration, deep
percolation, surface runoff and depth of irrigation water to be applied on a daily as well as a seasonal basis. It also simulates
daily ponding depth in the field. Both saturated and unsaturated water flow concepts were incorporated into the model to predict
deep percolation loss during wet and dry periods of the field. The model was validated using data collected from field experiments.
The details of model development and validation are outlined in this paper.
Received: 21 December 1999 相似文献
129.
Hans R. Kataria Jaipal S. Yadav Faquir C. Garg Rajendra K. Grover 《Pest management science》1985,16(4):337-340
2-Methoxyethylmercury chloride (MEMC) applied to cowpea seeds with Rhizobium provided little or no control of seedling rot caused by Rhizoctonia solani; similar treatment, but without Rhizobium, gave >40% control of disease. Treating seeds with quintozene and then with Rhizobium rendered the fungicide completely ineffective against R. solani infections; disease control was >70% when seeds were treated with quintozene only, and >60% when seeds were coated first with Rhizobium and then with quintozene; treatment with quintozene+Rhizobium gave about 25% control. Simultaneous treatment with Rhizobium considerably reduced the efficacy of captafol, chloroneb, carbendazim and thiophanate-methyl. Disease control by carboxin, benomyl and thiabendazole remained unaltered in the presence of Rhizobium, but only thiabendazole gave good control. Seeds treated with MEMC and Rhizobium produced seedlings without root nodules; nodulation was also decreased by captafol and by carboxin but six other fungicides had no effect. The implications of Rhizobium-fungicides interactions are discussed in the context of fungicidal control of root diseases. 相似文献
130.