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101.
102.
Adel Saberivand Ghodratollah Mohammadi Arash Javanmard 《Veterinary research communications》2010,34(6):541-548
The native breeds, because of their natural selection against harsh environment and adaptation to regional conditions are
important to resource-poor farmers and pastoralists. The molecular characterization of genetic variation is a fundamental
step to manage and conserve indigenous breeds. The aim of this study was to determine the genetic variation of Makui sheep.
Totally, 100 sheep (60 ewes, 10 ram and 30 lambs) were used in this study. Polymerase Chain Reaction (PCR) was performed using
microsatellite primers BM1329, OarAE101, OarFCB11, OarFCB128, OarFCB129, OarFCB20, OarFCB304, OarFCB5, OarHH35 and OarHH55
in a standard 25 μl reaction. All microsatellite loci were amplified and produced minimum 2 and maximum 14 alleles ranging
from 90 to 185 bp in size. The mean number of alleles for each locus was 6.8. Loci OarFCB128 and OarAE101 produced the highest
(8.5288) and the lowest (1.0304) effective number of alleles, respectively. The mean expected heterozygosity for all loci
was 0.6893 (range 0.0295–0.8837). The highest (2.12) and the lowest (0.07) Shanon Index was observed in OarFCB11 and OarAE101,
respectively. Only two (OarFCB5 and OarAE101) out of ten loci were in Hardy-Weinberg equilibrium. The present study was able
to demonstrate a reasonable genetic variation and polymorphism across all microsatellite loci studied in the Makui sheep. 相似文献
103.
A. G. Abdel-Sabour H. A. Obiadalla-Ali K. A. AbdelRehim 《Journal of Crop Science and Biotechnology》2010,13(1):53-60
The objective of this work was to evaluate the genetic variability among six cowpea (Vigna unguiculata) cultivars differing in their resistance to Callosobruchus maculatus (F.) weevil. Two resistant bean cultivars were used to compare between the sensitive, moderate tolerant, and high tolerant
cowpea cultivars. The differentiations were performed by using random amplified polymorphic DNA (RAPD) fingerprinting, protein
concentration and organic and non-organic components in seed coat. Six polymorphic primers were identified, resulting in different
informative bands. Based on polymorphic profiles, three clusters were formed. Clustering was mainly affected by the resistance
to weevil pest. The sensitive cowpea cultivars were separated in one group, the moderate tolerant and high tolerant cultivars
came in separate groups, and finally, the resistant bean cultivars separated clearly in one distinct group. The most interesting
result was represented by concentration of total protein in the seed coat. The protein concentration in the resistant bean
cultivars were approximately 50% less than concentration in each of the moderate tolerant and sensitive cultivars of cowpea.
Ferric ions were about 25% less than the moderate tolerant and sensitive cultivars. The concentrations of calcium and potassium
in seed coats were higher in the resistant beans than in cowpea cultivars. Cobalt was about four times higher in resistant
bean than in the sensitive and moderate tolerant cowpea cultivars, which may play a major role in seed resistance to weevil. 相似文献
104.
105.
A field experiment was conducted in 2011 and 2012 to study the effect of fertigation on yield, fruit quality and nutrient uptake of ‘Nabbut-Ahmar’ date palm cultivar grown in sandy loam soil. Three fertigation treatments were compared with traditional application. In traditional treatment (CT), the recommended dose [2300 g nitrogen (N), 1200 g phosphorus (P) and 1400 g/tree] was applied as a soil broadcast in three equal doses. The fertigation treatments, (T2), (T3) and (T4), represent all nitrogen, phosphorus and potassium (NPK) amounts of CT, 2/3 CT and 1/3 CT, respectively that were injected in twelve equal doses. The results showed that compared to CT, the fertigation treatments increased yield/palm by 41%, 31% and 18% for T3, T2 and T4, respectively. Beside the increase in yield, 33% and 66% of the applied fertilizers were saved by T3 and T4, respectively, compared with CT. Feritgation treatments had no negative impact on the overall fruit quality characteristics and even increased total soluble solids (TSS), soluble tannins and total phenols concentrations compared to the conventional fertilization. Availability of NPK increased by fertigation but without further increase in leaves and fruit. In conclusion applying 2/3 of the recommended dose of NPK fertilizers under dry land condition through fertigation maximize yield, quality and fertilizer use efficiency. 相似文献
106.
Adel Mohamed Robin M. Reich Raj Khosla C. Aguirre-Bravo Martin Mendoza Briseño 《林业研究》2014,25(1):87-95
This paper presents an approach based on field data to model the spatial distribution of the site productivity index (SPI) of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy (elevation, aspect and slope), soil attributes (pH, sand and silt), climate (temperature and precipitation zones) and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, Mexico. 相似文献
107.
Adel Jalili Younes Asri Shahbaz Yazdani Fatemeh Zarrinkamar Reza Safavi John G Hodgson Ken Thompson Mojtaba Pakparvar 《Biological conservation》2003,109(3):425-431
The Arasbaran Protected Area is an important but little studied nature reserve in NW Iran. In the past habitat heterogeneity and biodiversity have been threatened by over-exploitation; in the future depopulation may lead to partial abandonment. The soil seed bank was examined to see whether there are sufficient species represented as persistent seeds to reconstitute the vegetation in the event of habitat deterioration. There were differences between seed banks from different soils and vegetation types but essentially all soil seed banks contained few species and low densities of seed. Moreover, the species in the seed bank were unrepresentative of the vegetation. During future periods of changing land use it will be important to maintain the existing vegetation. There are however indications of successful recent conservation management. Annuals are abundant in the woodland seed bank but absent from the vegetation. The forest is recovering from the disturbance of collecting fire-wood. 相似文献
108.
Adel?UsmanEmail author Yakov?Kuzyakov Karl?StahrEmail author 《Journal of Soils and Sediments》2005,5(4):245-252
Background Aims, and Scope. Reducing heavy metal solubility and bioavailability in contaminated area without removing them from the
soil is one of the common practices in decreasing the negative impacts on the environment and improving the soil quality.
Therefore, our aim was to study the effect of clay minerals: Na-bentonite, Ca-bentonite, and zeolite applied to a contaminated
soil on immobilization of heavy metals, as well as on some soil parameters related with microbial activity.
Methods A soil derived from sewage sludge was incubated with clay minerals of either Na-bentonite, Ca-bentonite, or zeolite for 111
days (d). During the incubation experiment, concentrations of water soluble Zn, Cd, Cu, and Ni were measured after extraction
of 2 g air-dry soil with 50 ml of H2O for 2 h. After the water extraction, the soil sediment was extracted with 50 ml of 1
M NH4NO3 for 2 h to estimate the exchangeable amounts of heavy metals. Furthermore, soil microbial respiration, microbial
biomass C, Corg mineralization, metabolic quotient (qCO2), and inorganic N were also investigated.
Results and Discussion Water extractable and exchangeable forms of heavy metals were changed by incubation and addition of clay minerals. Incubation
of soil without addition of clay minerals (control) increased water extractable Cu by 12, 24 and 3.8% of initial content after
21, 62, and 111 d of incubation, respectively. The water extractable Zn decreased by 9% during 62 d of incubation and it tended
to increase by 14% at the end of the incubation, as compared with the initial soil. Water extractable Cd decreased by 71,
66 and 33% of initial content, and Ni decreased by 54, 70, and 58%, after 21, 62, and 111 d of incubation, respectively. During
the incubation experiment, the exchangeable form of all tested metals was decreased by incubation. The addition of clay minerals
led to a significant decrease in water soluble and exchangeable forms of heavy metals during the incubation experiment, resulting
in low metal extractability. The reduction in metal extractability was greater due to the addition of Na-bentonite or Ca-bentonite
than that due to the addition of zeolite. During the first 3 weeks after addition of clay minerals, the studied biological
parameters were not affected. However, as incubation progressed, the addition of Na- or Ca- bentonite led to a significant
increase in soil respiration, microbial biomass C, Corg mineralization, and inorganic N; and a significant decrease in qCO2.
This result is explained by sorption of heavy metals on Na-bentonite and Ca-bentonite and strong reduction of their toxicity.
Conclusions Our results clearly show that the addition of clay minerals, especially of Na-bentonite and Ca-bentonite, decreased the extractability
of four metals during incubation. The decreased metal extractability was accompanied by an increase of soil respiration, Corg
mineralization, microbial biomass C, and inorganic N and a decrease of metabolic quotient (qCO2), showing positive effect
of clay mineral addition on soil biological parameters.
Recommendations and Outlook The use of Na-bentonite and Ca-bentonite is promising tool for reduction the extractability and possible toxicity of heavy
metals in sewage sludge-contaminated soil. Therefore, the soils polluted with heavy metals may be ameliorated by addition
of clay minerals, especially Na-bentonite and Ca-bentonite. 相似文献
109.
Zusammenfassung Im Juni 1986 wurde im Irak eine Sammelreise durchgeführt. Landsorten von Getreide, Gemüsen und einigen anderen Kulturpflanzen konnten gesammelt werden; insgesamt 141 Proben. Die Generosion ist bei den Getreiden schon weit fortgeschritten. Durch die Einführung vieler neuer Gemüsesorten muß in den nächsten Jahren mit einem empfindlichen Verlust von Gemüse-Landsorten gerechnet werden. Das Sammelmaterial ist von großer Bedeutung für die Züchtungsforschung und Züchtung.
Collection of land-races of cultivated plants in Iraq, 1986
Summary A collecting mission was carried out in Iraq in June 1986. Land-races of cereals, vegetables and some other crops could be collected, altogether 141 accessions. Genetic erosion is advanced in cereals. Because of the introduction of many new cultivars a severe loss of vegetable land-races has to be expected in the next years. The material collected is important for breeding research and breeding purposes.
1986
1986 , , . 141 . ¶rt;. - , , , . , .相似文献
110.
A compilation of some useful approaches used for the obtention of the minimum potential between interacting flat clay double layers is given. Values of the minimum potential obtained from published nomograms, tables and equations are compared. The effect of dissimilar double layers on the potential is also illustrated. 相似文献