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91.
Sudhir Shukla S. P. Singh H. K. Yadav A. Chatterjee 《Genetic Resources and Crop Evolution》2006,53(3):533-540
The opium latex of 1470 individual plant samples of 98 germplasm lines were screened for five major economic alkaloids. The
alkaloids profile showed that morphine content ranged from 9.20–20.86% with an average of 15.00 ± 0.267. Codeine ranged from
1.69–6.48% with arithmetic mean of 3.35 ± 0.091, thebaine from 0.52–7.95% with an average of 2.27 ± 0.116. Narcotine ranged
from 8.79–17.97% with an average 8.79 ± 0.266 and papaverine content ranged from 0.00–6.07% with an average 1.18 ± 0.167 in
over all the germplasm lines. The content of different alkaloids categorized into class interval which exhibited that maximum
number of plants and accessions for morphine content fall in group of 10–15% followed by 15–20%, for codeine content in group
of 2–4% followed by 4–6%, for thebaine content in 1–2% followed by 2–4%, for narcotine in 5–10% followed by 10–15% and for
papaverine content 0–2%. 24 germplasm lines had morphine content above 16.0%. Similarly, 37 germplasm lines for codeine and
13 for thebaine showed consistently high content, i.e., above 3%. 33 germplasm lines had narcotine content above 9% and 20
lines exhibited papaverine content above 2%. Line BR 316 was found unique having thebaine content 6.27–9.33%. The probable
reasons of increase or decrease of different alkaloids based on their biosynthetic pathway has been discussed in detail. 相似文献
92.
Himani Singh Ajey Singh Imtiyaz Hussain Vijaya Yadav 《Archives of Agronomy and Soil Science》2016,62(10):1425-1436
In the present study, attenuation of isoproturon (IPU) toxicity by salicylic acid (SA) was observed. Seven-day-old seedlings of pea (Pisum sativum L. cv. Azad P-1) were treated with 10 mM IPU. IPU influenced physiological and biochemical parameters. IPU significantly inhibited growth variables like shoot and root height, fresh and dry biomass of the pea. The contents of carotenoids, chlorophylls, protein and activity of nitrate reductase were inhibited significantly. IPU enhanced the accumulation of H2O2, ion leakage and lipid peroxidation due to induction of oxidative stress in pea. The activities of antioxidant enzymes, namely superoxide dismutase, catalase and ascorbate peroxidase increased while the activities of guaiacol peroxidase decreased. However, exogenous SA regulated the toxic effects of IPU. The indices of oxidative stress appeared to be alleviated by SA. Pigment content and activities of enzymes increased approximately up to the level of control. IPU caused non-target phytotoxicity to P. sativum. The natural growth regulator/allelochemical has potential to overcome the adverse effects caused by IPU.
Abbreviations: CAT: catalase; EL: electrolyte leakage; IPU: isoproturon; LP: lipid peroxidation; MDA: malondialdehyde; NR: nitrate reductase; POD: guaiacol peroxidase; SOD: superoxide dismutase; TCA: trichloroacetic acid 相似文献
93.
O. P. Yadav 《Euphytica》1994,78(1-2):77-80
Summary The threshing percentage (TH%) has been suggested as a selection criterion to identify the pearl millet (Pennisetum glaucum (L.) R.Br.) lines with improved ability to fill and set grains under water limiting conditions. In this study, eight genetically diverse pearl millet inbreds and their 28 crosses produced by half diallel crossing design were used to examine range in TH%, to evaluate general combining ability (GCA) of parents and specific combining ability (SCA) effects of crosses. The results showed significant variation among parental lines for TH%. The inbreds differed for their GCA effects and crosses for their SCA effects. Parents with high TH% and positive GCA effects were identified. The results of the study revealed that both additive and dominance components, with the preponderance of later, were important in the inheritance of TH%. Heritability in narrow sense was moderate (55%) indicating that selection for high TH% might be effective. 相似文献
94.
Inheritance of resistance to the fruit borer, Heliothis armigera Hübner in tomato was studied in TWO interspecific crosses. L. hirsutum f. gLabratum‘B 6013′. a fruit borer-resistant parent, was crossed with two susceptible L. esculentum varieties ‘HS 101’ and. ‘HS 102′. Six generations of two crosses were evaluated for percentage fruit: infestation (on a number basis) and the estimates of the gene effects were derived from the generation mean using a three parameter model A preponderance of additive gene effects was found for this trait. Heritability in the narrow sense was observed to be high indicating the fixable nature of the character. 相似文献
95.
Inheritance of Cercospora leaf spot resistance in mungbean was studied in 20 crosses involving crosses of resistant × susceptible, resistant × resistant, susceptible × susceptible lines. 3:1 ratio was observed in all 14 F2s involving resistant × susceptible parents. The inheritance of Cercospora leaf spot resistance is thus controlled by a single recessive gene. Our results are contradictory to observations of Thaklk et al. (1977 a, b) who found monogenic dominant inheritance of Cercospora leaf spot resistance in mungbean. 相似文献
96.
Three commercial Indian wheat varieties —‘Sonalika’, ‘Kalyansona’ and ‘Janak’ were used to develop homogeneous and heterogeneous lines for leaf rust resistance, utilizing diverse sources of resistance from fourteen donors. Four kinds of multilines were developed to study coefficients o: infection, areas under disease progress curves (AUDPC), rates of spread and grain yields over their component means. Heterogeneous populations showed minimum coefficients of infection at initial as well as final stages, which were less than or equal to the resistant component even in dirty multilines carrying up to 50 % susceptible populations. Large reductions in coefficients of infection and in AUDPC were also observed. Rate of spread was independent of coefficient of infection and AUDPC. Grain yield advantage over both component means and recurrent parents was higher in clean multilines. The significance of the use of multilines in limiting losses due to disease is discussed. 相似文献
97.
Summary Genetic divergence in 110 population (20 parents and 90 F1 hybrids) of opium poppy was studied by multivariate analysis. All the entries were grouped in 14 clusters. Out of 20 parents,
ten were accumulated in one cluster and rest 10 distributed over seven clusters. Estimates of cluster distance showed that
maximum intra-cluster distance was in -cluster IX (25.62) followed by cluster I (22.41), V (22.23) and IV (21.06). The inter
cluster distances varied from 16.62 (between cluster XII and XIV) to 195.10 (between cluster IV and IX). The cluster analysis
indicated substantial diversity among the parental genotypes, which had the potential to release considerable variation in
their crosses. The first four principal components (PCs) with eigen values >1 accounted for 68% of variation among the population.
The first and second components could account for 29 and 20% of the total morphological and alkaloidal variations, respectively.
The PC1 was closely related to yield and yield related traits. The characters contributing greatest positive weight on PC1
were opium yield, plant height, stem diameter, capsule weight/plant and seed yield/plant. The possibilities of relationship
between genetic divergence, F1 performance, heterosis and GCA of parents have been explored. 相似文献
98.
Rajasekhar K. V. Prakash B. Vijaya Lakshmi K. Rama Rao S. V. Raju M. V. L. N. 《Tropical animal health and production》2020,52(5):2297-2302
Tropical Animal Health and Production - The experiment was conducted to study the effect of feeding diets with quality protein maize (QPM) along with cottonseed meal (CSM) and guar meal (GM) on... 相似文献
99.
Ashish Bashyal Sandeep Shrestha Kishor P. Luitel Bhupendra P. Yadav Bed Khadka Jeffrey W. Lang Llewellyn D. Densmore 《水产资源保护:海洋与淡水生态系统》2021,31(9):2594-2602
- The Critically Endangered gharial (Gavialis gangeticus) residing within Bardiya National Park (BNP) in Nepal constitutes the sixth major sub-population of this unique lineage; however, this population is not well studied. A 46 km protected stretch of the Babai River and a 60 km stretch of the Karnali River in and around BNP were surveyed for gharials in early 2017 and in 2019.
- Gharial counts in 2017 – 17 from the Babai and one from the Karnali rivers – consisted of 10 adults, five sub-adults and three juveniles. In 2019, 19 gharials were counted – 18 for the Babai and one for the Karnali – comprising 11 adults, six sub-adults and two juveniles. In the Babai River within BNP, four breeding groups were identified. Gharials in BNP prefer sandy vs. rocky banks for basking and completely avoid sand-grass and clay banks. Habitat preference did not vary with size class.
- Protected stretches of both rivers inside BNP (76 km) have resident gharial, intact habitats and few human threats. In contrast, the unprotected stretch of the Karnali (30 km) is threatened by boulder quarrying, sand mining and unlicensed fishing, and is avoided by gharials despite the availability of habitat.
- This study established baseline data, including indices of population size, distribution and habitat preferences, and documented resident gharials that are breeding in the Babai River in BNP. The conservation of this Babai population is crucial for the species’ survival in BNP.
- Based on this study, we recommend the following conservation actions on the Babai stretch: (a) determine hatching success; (b) assess juvenile recruitment; (c) consider supplementation by releasing captives; (d) study riverine features important as baselines; (e) accommodate upstream movements on the protected Babai stretch; and (f) protect the downstream Babai outside the boundary of the BNP.
100.
S. Mandal Sangita Yadav Ranbir Singh Gulnaz Begum Poonam Suneja M. Singh 《Genetic Resources and Crop Evolution》2002,49(6):551-556
Mean individual fatty acid concentration among differentspecies of the family Cruciferae are not similar because of the presence ofdifferent kind of significant relationship among the individual fatty acids.Brassica napus L., Sinapis alba L.,Raphanus caudatus L.f. Raphanus sativusL. and B. nigra (L.) Koch arecomparatively low erucic acid (<40%) containing species. Crambeabyssinica Hochst. ex. R. E. Fries collections gave as high as 60%erucic acid. Low erucic acid concentration was found associated with thepresence of high level of palmitic and oleic acid concentrations. Erucic acidconcentrations were found varied within the range of 42 to 57% among thecollections of Brassica rapa L. and B.carinata A. Braun. All the collections ofB. nigra (L.) Koch were found to havehigher proportion of linoleic acid than the corresponding oleic acidconcentration. Linolenic acid concentrations of B.nigra (L.) Koch was also higher in comparison to otherspecies of the Cruciferae. Raphanus collections were foundto contain higher levels of total saturated fatty acids as well as eicosenoicacid. Oil content of the total collections under present study did not show anysignificant relationship either with linolenic acid or with erucic acidconcentration. But significant positive relationship was observed between totaloil and erucic acid level within the collections of B.juncea Czern. & Coss. Similarly significant negativecorrelation was observed between total oil and linolenic acid content inBrassica rapa L. ssp. trilocularis (Roxb.) Hanelt, yellow sarson. 相似文献