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131.
L. Krishnamurthy Rachid Serraj Kedar Nath Rai C. Tom Hash Abdullah J. Dakheel 《Euphytica》2007,158(1-2):179-188
Crop tolerance to salinity is of high importance due to the extent and the constant increase in salt-affected areas in arid
and semi-arid regions. Pearl millet (Pennistum glaucum), generally considered as fairly tolerant to salinity, could be an alternative crop option for salt affected areas. To explore
the genotypic variability of vegetative-stage salinity tolerance, 100 pearl millet lines from ICRISAT breeding programs were
first screened in a pot culture containing Alfisol with 250 mM NaCl solution as basal application. Subsequently, 31 lines
including many parents of commercial hybrids, selected from the first trial were re-tested for confirmation of the initial
salinity responses. Substantial variation for salinity tolerance was found on the basis of shoot biomass ratio (shoot biomass
under salinity/ non-saline control) and 22 lines with a wide range of tolerance varying from highly tolerant to sensitive
entries were identified. The performance of the genotypes was largely consistent across experiments. In a separate seed germination
and seedling growth study, the seed germination was found to be adversely affected (more than 70% decrease) in more than half
of the genotypes with 250 mM concentration of NaCl. The root growth ratio (root growth under salinity/control) as well as
shoot growth ratio was measured at 6 DAS and this did not reflect the whole plant performance at 39 DAS. In general, the whole
plant salinity tolerance was associated with reduced shoot N content, increased K+ and Na+ contents. The K+/Na+ and Ca++/Na+ ratios were also positively related to the tolerance but not as closely as the Na+ content. Therefore, it is concluded that a large scope exists for improving salt tolerance in pearl millet and that shoot
Na+ concentration could be considered as a potential non-destructive selection criterion for vegetative-stage screening. The
usefulness of this criterion for salinity response with respect to grain and stover yield remains to be investigated. 相似文献
132.
Kedar Nath Mohanta Satyendra Nath Mohanty Joykrushna Jena & Narottam Prasad Sahu 《Aquaculture Research》2007,38(16):1702-1713
Six iso‐nitrogenous (30% crude protein) and iso‐energetic (15 kJ g−1) diets were prepared using different oil cake sources, viz. groundnut, soybean, sunflower, sesame, mustard and mixed oil cakes as major ingredients, and protein sources along with a minimum of 5% fish meal in each diet and were fed to silver barb Puntius gonionotus fingerlings (16.20±0.11 g) ad libitum four times a day close to an apparent satiation level for a period of 60 days to determine the effect of diets on growth, nutrient utilization, apparent digestibility coefficient (ADC) of the nutrients in the diets, gut enzyme activity, muscle nucleic acid content and whole‐body chemical composition of fish. Significantly higher (P<0.05) weight gain, specific growth rate, protein efficiency ratio, nutrient retention, ADC of nutrients in the diets, DNA:RNA ratio, protease and amylase activity with lower (P<0.05) feed:gain values were recorded in fish‐fed groundnut and soybean oil cake‐based diets than other diets tested. Among the dietary treatment groups, significantly higher (P<0.05) whole‐body protein, lipid and energy were also found in groundnut oil cake‐ and soybean oil cake‐based diets. The study suggests that the groundnut and soybean oil cake‐based diets, which led to significantly higher (P<0.05) growth and nutrient utilization than the other oil cake‐based diets in P. gonionotus fingerlings, may be used for pond culture of this species. 相似文献
133.
Oocyte growth in most oviparous vertebrates including fish is due to the formation of yolk, and eggshell proteins (zona radiata
proteins). Zonagenesis leads to the formation of zona radiata proteins in oocytes, which play an important role during oogenesis,
whereas vitellogenesis leads to the formation of yolk in oocytes through a series of events during which the yolk precursor
protein vitellogenin (Vg) is synthesized and secreted from liver into blood from where it is sequestered into the developing
oocytes and thereafter proteolytically cleaved to form yolk proteins (YPs) and finally deposited in the ooplasm. Much research
has been done in many fish species with respect to the number and nature of Vg and YPs and their probable functions during
fish reproduction. Recent findings of multiplicity of Vg molecules in fishes reject the earlier view of a single-Vg model
and have led scientists to explore the functions of individual Vg and their YP derivatives, lipovitellin, phosvitin, and β′-component.
Two distinct types of Vg or Vg genes, containing or encoding the three YPs, have been detected in many teleosts. A third unusual,
incomplete, phosvitin-poor Vg has been described recently in many fishes. In comparison to much of the information on vitellogenesis
in many fishes very little is known for Indian fishes. In India research has been done in a few species such as the catfish,
Heteropneustes fossilis and Clarias batrachus, the murrel, Channa punctatus and the Indian major carps, Labeo rohita and Cirrhinus mrigala. Immunological and biochemical analyses suggest the occurrence of multiple forms of Vg and their YP derivatives. The synthesis
and incorporation of Vg are regulated by gonadotropin (GTH) and estradiol-17β (E2). A differential role between estrone (E1) and estriol (E3) has been demonstrated for Vg synthesis. Enzyme-linked immunosorbent assays (ELISAs) for Vg have been developed to measure
plasma Vg. Finally the different roles of Vg1 (HAI) and Vg2 (HAII) on vitellogenesis have been demonstrated. However, more
research remains to be carried out in other fish species with respect to the number and nature of Vg and YPs and their genes
in order to describe their reproductive functions. 相似文献
134.
The impact of fiber friction, yarn twist, and splicing air pressure on mechanical and structural properties of spliced portion
have been reported in the present paper. The mechanical properties include the tensile and bending related properties and,
in the structural properties, the diameter and packing density of the splices are studied. A three variable three level factorial
design approach proposed by Box and Behnken has been used to design the experiment. The results indicate that there is a strong
correlation between retained spliced strength (RSS) and retained splice elongation (RSE) with all the experimental variables.
It has been observed that RSS increases with the increase in splice air pressure and after certain level it drops, whereas
it consistently increases with the increase in yarn twist. The RSE increases with the increase in both fiber friction and
yarn twist. It has also been observed that the yarn twist and splicing air pressure have significant influence on splice diameter,
percent increase in diameter and retained packing coefficient, but the fiber friction has negligible influence on these parameters.
Yarn twist and splicing air pressure has a strong correlation with splice flexural rigidity, where as poor correlation with
retained flexural rigidity. 相似文献
135.
A pot experiment was conducted to evaluate different arbuscular mycorrhiza sps. (AM) for their effect on plant growth, yield and nutrient uptake by wheat. All the AM fungal sps. significantly enhanced all the plant parameters and nutrient uptake by the plant. A positive correlation was observed between percent root colonization by AM fungi and most of the plant parameters studied. Glomus macrocarpum giving best results was selected for studying interactive effect with Azotobacter, Azospirillum (well-known PGPRs), and Flavobacterium and Proteus vulgaris (less studied PGPRs). All the PGPRs significantly increased most of the plant parameters studied and their combination with AMF had a synergistic effect. Amongst PGPRs, Flavobacterium gave best response both singly and in combination with AMF and thus, is a potential new bioinoculant for wheat. Application of 120 kg nitrogen (N) ha?1was the best treatment. Inoculation with most of the PGPRs gave better response than 60 kg N ha?1. 相似文献
136.
Ghosh Arkendu Dey Koyel Hassan Md. Abu Bauri Fatik Kumar Das Bikash Chandra Bhowmick Nilesh Dey Amarendra Nath Das Soumitra Sahu Pradip Kumar 《Genetic Resources and Crop Evolution》2022,69(7):2585-2604
Genetic Resources and Crop Evolution - Semecarpus anacardium L. is a potential underutilized edible, highly nutritious fruit crop with ample medicinal properties grown in some localized pockets of... 相似文献
137.
Total seed storage proteins of five species of Celosia (14 taxa) have been compared by sodium dodecyl sulphate polyacrylamide gel electrophoresis. Relative similarities between the taxa were estimated by Jaccard's similarity index and cluster analysis was performed to produce a UPGMA dendrogram which divides 14 taxa into two groups while C. trigyna holds an isolated position. One group includes 4x C. cristata and C. plumosa, wild 8x C. argentea and 12x C. whitei and the other separates four accessions of 4x C. argentea. This raises a doubt regarding 4x types of C. argentea being the direct progenitors of the cultivated types. 相似文献
138.
139.
Abrar Juhar Mohammed Makoto Inoue Rose Jane Peras Tapan Kumar Nath Mohammed Jashimuddin Juan M. Pulhin 《Small-Scale Forestry》2016,15(2):213-227
This study demonstrates the potential of transformation strategy (an approach that emphasizes strengthening interdependence among social and ecological systems) to rehabilitate degraded land by examining two cases in Bangladesh and one in the Philippines. The study considers the benefits obtained from forests and forest-related activities in the form of income and energy sources as key parameters to link the social system (local people) with the ecological system (forest). Qualitative and quantitative analysis of data on land use and socio-economic changes indicates that the transformation strategy improved both the wellbeing of local people and forest cover. In the case of the Philippines, social and ecological linkages were found to be strong, with local people rehabilitating the degraded land while also obtaining a high proportion of their total income from the activity. For the two Bangladesh cases, however, the level of dependency on the forest for livelihood declined as local people used their income from the forest and forest-related activities for diversification to non-forest activities. 相似文献
140.
A survey of medicinal plants used by the ethnic communities of Dibru-Saikhowa Biosphere Reserve in Northeast India has been reported. Fifty-five plant species belonging to 34 families and 52 different genera were included. For each plant species, botanical name, vernacular name, part(s) used, popular medicinal use, forms of preparation and applications of the herbal remedies are provided. 相似文献