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141.
Dhananjay Kumar Tewary Anu Bhardwaj Anuj Sharma Arun Kumar Sinha Adarsh Shanker 《Journal of pest science》2006,79(4):209-214
In the light of recent increased interest in developing plant based secondary chemistry into products suitable for integrated pest management, the objective of the present study was to investigate the bioactivity in field simulated conditions and structure–activity relationship of some natural phenylpropenes and their related analogues (1–6) against Aphis craccivora. The activities of different compounds varied depending on the substitution of the functional groups and the side chain attached to the aromatic ring of the phenylpropene. Dimethyleugenol (5) showed maximum activity among all tested phenylpropenes with LC50 values 880 and 2,047 ppm against nymphs and adults respectively. Present study showed that phenylpropenes appear to be promising natural insecticides and may hold potential for identification of new lead structures against A. craccivora. The activity of the most active phenylpropene (5) was comparable with that of the chemical pesticide (dimethoate). 相似文献
142.
Rajiv Krishna Parvathaneni Senthil Natesan Ashok Arunachalam Devaraj Raveendran Muthuraja Rajasree Venkatachalam Arun Prathap Subramani Pugalendhi Laxmanan 《Journal of Crop Science and Biotechnology》2011,14(1):39-43
In the present investigation, 13 Cucumis genotypes from different geographical areas of India were screened for genetic diversity using 19 morphological traits and
15 ISSR primers. The analysis of morphological traits grouped the accessions into six clusters. Cluster V contained the maximum
number of genotypes namely Kanivellari, Long Green, Andaman Local, Perundurai Local, and Sempatti Local. Clusters I and VI
contained the minimum number of genotypes. Among all the characters, the highest mean value was observed in fruit length (23.38)
and the lowest mean value was observed in stripes on the blossom end (1.31). The 15 ISSR primers generated 109 polymorphic
alleles. The average number of ISSR alleles generated was 8.3 per primer and the level of polymorphism was 87.20%. The ISSR
primer UBC 825 was highly informative with a PIC value of 0.8934. The 13 genotypes were grouped into six clusters based on
ISSR markers. Cluster III contained the maximum number of genotypes, namely Kanivellari, Sankagiri Local, Perundurai Local,
Long Melon, and Sempatti Local, while Clusters I, II, IV, and V (Karur Local, Andaman Local, Edapaddi Local, and N 78, respectively)
contained the minimum number of genotypes. The ISSR profile generated genotypes specific allele namely, UBC 812700bp and UBC 8121000bp for Cluster VI which contained Cucumis genotypes collected from the northern part of India. Similarly, UBC 808 produced specific allele UBC 808650bp formed in Cluster III which contained genotypes collected from Tamil Nadu and Kerala. 相似文献
143.
Sovan Debnath Raj Narayan Anil Kumar Arun Kishor Desh Beer Singh 《Soil Science and Plant Nutrition》2020,66(3):489-498
ABSTRACT Soil fertility in many parts of the north?western Himalayan region (NWHR) has declined owing to accelerated nutrient mining under existing crop regime. Therefore, this study aimed to assess effect of the predominant horticulture?based land uses on soil fertility and health in mid and high hills of NWHR. Soil samples (0?20 cm) were collected, analyzed for different soil chemical attributes (pH, electrical conductivity, organic C, available primary-, secondary-, and micro-nutrients), and compared across five key land uses: perennial grass (PG), peach orchard (PO), apple orchard (AO), field vegetable farming (VF), and protected vegetable farming (PV). Soils of the investigated land uses were neutral to near neutral in soil reaction (6.3?6.8) except field vegetable and protected vegetable farming. Amount of soil organic C and labile organic C was significantly higher (p ≤ 0.05) in soils of apple orchards (18.6 g kg?1 and 687.3 mg kg?1, respectively) and peach orchards (20.4 g kg?1 and 731.3 mg kg?1, respectively) over others. An abrupt and significant increase in Olsen-P was recorded in soils of field vegetable farming (17.1 mg kg?1) and protected vegetable farming (13.0 mg kg?1), which shifted their nutrient index (NI) of P in to high category (≥ 2.33). The concentration of mineralizable-N in soil was statistically at par in soils under perennial grass and fruit orchards, while protected vegetable farming showed maximum soil mineralizable-N content (115.5 mg kg?1) and NI of nitrogen (1.83). The NI was in high category (≥ 2.33) for copper, iron, and manganese in majority of the land uses. In view of the results, temperate fruit?tree based land uses are benign in up?keeping soil fertility and soil health, and needs promotion on large scale. Additionally, policies to create incentives for the build-up of soil organic matter and replenishment of the depleted soil macro and micro nutrients in vegetable-farmed lands are warranted. 相似文献
144.
145.
Angshuman Biswas Mitali Pramanik Samita Kundu Sumedha Roy Jhuma De Arun Kumar Ray 《Fish physiology and biochemistry》2006,32(1):73-81
Triploid Heteropneustes fossilis (Bloch) showed sterility and higher growth potential than the normal diploid fish. Activities of some metabolic enzymes such
as cytosolic NADP-malate dehydrogenase (NADP-MDH), mitochondrial NAD-malate dehydrogenase (NAD-MDH) and glutamate pyruvate
transaminase (GPT) were evaluated in liver, brain and kidney along with glucose-6-phosphate dehydrogenase (G-6-P D) in ovary
of female triploid catfish. Activities of these enzymes showed distinct seasonal periodicity, mostly with highest activities
in prespawning and spawning periods, in both diploid and triploid catfish but differed in magnitude. In triploid liver, GPT
showed higher activity than the diploid counterpart in prespawning and spawning periods. On the contrary, mitochondrial NAD-MDH
and cytosolic NADP-MDH in this organ showed a consistent lower activity than the diploid in all stages or in some stages of
reproductive cycle respectively. Interestingly, none of the enzymes in brain and kidney of triploid female catfish showed
significant changes in comparison to the diploid counterpart. The triploid ovary maintained a significantly lower level of
G-6-P D activity throughout the resting, preparatory and pre-spawning periods compared to the diploid ovary. Lower level of
malic enzymes (NAD-MDH and NADP-MDH) in liver and G-6-P D in ovary are in close synchrony with lower level of estradiol-17β
in plasma of female triploids as found in earlier study. 相似文献
146.
Sangbrita Saha Raj Narayan Roy Sukanta Kumar Sen & Arun Kumar Ray 《Aquaculture Research》2006,37(4):380-388
Isolation and characterization of cellulase‐producing aeorobic bacterial flora in the intestine of omnivorous tilapia (Oreochromis mossambica) and phytophagous Chinese grass carp (Ctenopharyngodon idella) have been carried out using selective carboxymethylcellulose‐agar (CMC‐agar) medium. The cellulolytic activity was measured both qualitatively and quantitatively. It was found that the ability of different strains in degrading cellulose varies within a wide range. Among the strains isolated from the gut of each test fish, TM1 and CI3 isolated from O. mossambica and C. idella, respectively exhibited maximum cellulolytic activity (67.02 and 35.8 U mL?1 respectively). Pure cultures of these strains were selected for morphological, physiological and biochemical characterization. On the basis of these tests, the isolated strains were identified as Bacillus circulans (TM1) and Bacillus megaterium (CI3). Both the strains are rod‐shaped, motile and show better temperature (15–42°C) and pH (5–11) tolerance. The selected strains were further quantitatively assayed for amylase and protease activities. Maximum amylase and protease activities were exhibited by TM1 and CI3 respectively. Information generated from the present study might contribute towards better‐feed formulation incorporating plant ingredients. 相似文献
147.
ABSTRACT Meiotic investigations were carried out in four different accessions of Balanites aegyptiaca (L.) Del. collected from various parts of Rajasthan, India. Chromosome associations, chiasma analysis and distinct pattern of chromosome/chromatids at anaphase I and II were studied in detail. The study revealed that all the accessions had the gametic chromosome number, except one (B. aegyptiaca BSJO-25160) that had n = 18. BSJO-25160 accession was characteristic in exhibiting chimeric nature as revealed through chromosome mosaicism, which resulted in variant chromosome number ranging from n = 9 to n = 16 in different pollen mother cells analyzed. The evolutionary implications of chromosome mosaicism/chimerism and its role in the development of anueploid series are discussed in detail. 相似文献
148.
Suma Arun Dev E. M. Muralidharan P. Sujanapal M. Balasundaran 《Annals of Forest Science》2014,71(4):517-522
Context
East Indian sandalwood (Santalum album L.) in commercial markets is highly prone to adulteration. A number of cases were registered with regard to the adulteration of East Indian sandalwood, but the lack of technical tools for the precise species identification of the source wood stalled most of the court cases.Aims
The standard DNA barcode regions, the rbcL, matK and trnH-psbA chloroplast genomic sequences recommended by the Consortium of Barcode of Life (COBOL) were analysed to distinguish wood adulterants of East Indian sandalwood.Methods
Standard polymerase chain reactions with COBOL recommended primers were performed for all three barcode loci. The PCR products after gel elution were sequenced and alignments were performed using CLUSTALX.Results
Single nucleotide polymorphisms (SNPs) identified with rbcL and trnH-psbA sequences of Erythroxylum monogynum Roxb. as well as with matK sequences of Osyris wightiana Wall ex. Wight could be efficiently utilized for the detection/monitoring of East Indian sandalwood adulterants. Among the two common adulterants O. wightiana and E. monogynum, the former was more similar to S. album and grouped together in the dendrogram.Conclusion
The study recommends the exploitation of DNA barcoding technique using standard barcodes to trace sandalwood timber adulterants. 相似文献149.
Brown stink bugs, Euschistus servus, are an important early-season pest of field corn in the southeastern United States. Feeding in the early stages of corn development can lead to a number of growth deformities and deficiencies and, ultimately, a reduction in yield. An observational and two experimentally manipulated trials were conducted in 2017 and 2018 to 1) determine optimal timing for assessing brown stink bug damage, 2) assess the level of damage from which yield compensation can occur, and 3) examine the relationship between brown stink bug density and early-season damage and yield. Fields were identified with infestations of brown stink bugs and a damage rating system for early stages of corn was established. Varying rates of brown stink bug densities were introduced using field cages and damage was assessed throughout the season. The density and duration of stink bug infestations were critical factors for damage potential, with each day of active feeding per plant resulting in a loss of ~14 kg/ha in yield. The level of damage in early stages of corn was categorized into easily identifiable groups, with only the most severe damage leading to a reduction in yield. Moderate and minimal feeding damage did not result in yield loss. This study emphasizes the need for early and frequent scouting of corn to determine the risk of damage and yield loss from brown stink bugs. Results from this study can be used to help develop management programs for brown stink bugs in the early vegetative stages of field corn. 相似文献
150.
Conventional textile based wound dressing materials are cost effective and highly absorbent, but when used alone fails to provide optimal wound healing conditions like homeostasis, non-adherence, maintenance of a moist wound bed, etc. Electrospun polymer web meets the requirements outlined for wound healing, by their microfibrous structures provide suitable environment for wound healing apart from the function of polymers. In this study, blends of soy protein isolate (SPI) and poly(ethylene oxide) (PEO) nano fiber web was prepared by electro spinning process. The developed blended nano fiber web was subjected to SEM, FTIR to evaluate fiber size and functional properties respectively. The Moisture vapour transmission rate (MVTR) result shows the blended electrospun web gives suitable mosit environment over wound bed such as the MVTR is 2994 g/m2/day. The blended electrospun web gives positive result on antimicrobial activity. The effect of SPI/PEO blended electrospun web on wound healing was experimented with female wistar rats and the blended electrospun web shows excellent result on wound healing by the growth of new epithelium without any significant adverse reaction. Forming of SPI/PEO electrospun fiber was fulfilled many critical elements desirable in a wound material. 相似文献