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51.
Evidence suggests that religion is an important driver of peoples’ attitudes toward nature, but the link between religion and carnivore conservation is poorly understood. We examined peoples’ attitudes in Buddhist (= 83) and Muslim communities (= 111) toward snow leopards (Panthera uncia) and wolves (Canis lupus) in Ladakh, India. We found that the effect of religion on attitudes was statistically nonsignificant, and was tempered by gender, education, and awareness of wildlife laws. Even though religion by itself was not an indication of an individual’s attitude toward large carnivores, the extent to which he/she practiced it (i.e., religiosity) had a positive correlation with pro-carnivore attitudes in the case of Buddhist but not Muslim communities. Our findings indicate that it may be useful to integrate locally relevant religious philosophies into conservation practice. However, the emphasis of conservation messaging should vary, stressing environmental stewardship in the case of Islam, and human–wildlife interdependence in the case of Buddhism.  相似文献   
52.
A Serological Survey for Brucellosis in Canadian Swine   总被引:1,自引:1,他引:0       下载免费PDF全文
The results of a survey which included the testing of 21,275 blood samples collected at various slaughter houses are described.

Sixty-three herds had a single reactor with a titre of 1:100 or higher to a tube or plate agglutination test. Investigations in forty-five of these herds failed to detect the presence of brucellosis in the remaining mature swine.

The prompt slaughter of the reactors may have eliminated possible sources of infection.

  相似文献   
53.
54.
The aim of the present study was to assess the genetic variation and establish the relationship amongst the three Indian zebu cattle breeds using 20 bovine‐specific microsatellite markers. A total of 136 unrelated DNA samples from Sahiwal (SC), Hariana (HC) and Deoni (DC) breeds of cattle were genotyped to estimate within and between breed genetic diversity indices. The estimated mean allelic diversity was 5.2, 6.5 and 5.9 in SC, HC and DC, respectively, with a total of 167 alleles. The average observed and expected heterozygosity for the population varied from 0.42 (SC) to 0.59 (DC), and from 0.61 (SC) to 0.70 (DC), respectively. Low values of genetic variability estimates were observed in SC when compared with DC and HC, indicating some loss of variability because of its relatively small population size. From global F‐statistics a significant deficit of heterozygotes of 24.2% (p < 0.05) was observed for each one of the analysed breeds whereas the total population had a 32.8% (p < 0.05) deficit of heterozygotes. The FST estimates demonstrated that approximately 88.7% of the total genetic variation was because of the genetic differentiation within each breed. Pair‐wise breed differentiation, Nei's standard and DA genetic distance estimates revealed relatively close genetic similarity between HC and DC in comparison with SC. In the UPGMA‐based phylogenetic tree constructed from the genetic distances, HC and DC were grouped together in one cluster and SC in the other. The estimated time of divergence suggested a separation time of approximately 776 years between DC and HC, and a comparatively longer period (1296 years) between DC and SC.  相似文献   
55.
The genetic structure of three Indian sheep breeds from two different geographical locations (Nali, Chokla from north‐western arid and semi‐arid region; Garole from eastern saline marshy region) of India was investigated by means of 11 ovine‐specific microsatellite markers as proposed in FAOs MoDAD programme. Microsatellite analysis revealed high allelic and gene diversity in all the three breeds. Nali sheep showed higher mean number of alleles and gene diversity (6.27 and 0.65) than Chokla (5.63 and 0.64) and Garole (5.63 and 0.59). High within population inbreeding estimates observed in the three breeds (FIS, Chokla = 0.286, Nali = 0.284, Garole = 0.227) reflected deficit of heterozygotes. The overall estimates for F‐statistics were significantly (p < 0.05) different from zero. High values of FST (0.183) across all the loci revealed substantial degree of breed differentiation. Based on pair wise FST and Nm between different breeds, Nali and Chokla (FST = 6.62% and Nm = 4.80) were observed to be the closest followed by Garole and Nali (FST = 20.9% and Nm = 1.80), and Garole and Chokla (FST = 21.4% and Nm = 1.71). In addition, genetic distance estimates, phylogeny analysis and individual assignment test used to evaluate interbreed genetic proximity and population structure also revealed substantial genetic differentiation between Garole and the other two Rajasthani (Nali and Chokla) sheep. This divergent status of Garole sheep indicated genetic uniqueness of this breed suggesting higher priority for its conservation.  相似文献   
56.
A series of available phosphorus (Olsen) levels ranging from 10 to 40 ppm were achieved in a semi-arid soil. The influence of the levels of phosphorus on the symbiotic interaction between two subtropical tree species, Acacia nilotica and Albizzia lebbeck, and a mixed inoculum of indigenous arbuscular mycorrhizal (AM) fungi was evaluated in a greenhouse study. The extent to which the plant species depended on AM fungi for dry matter production decreased as the levels of soil P increased, but the degree of this decrease differed in the two species tested. Acacia nilotica colonized by AM fungi showed a significant increase in shoot P and dry matter at a soil P level of 10 ppm whereas in Albizzia lebbeck, such increase occurred at 20 ppm. Mycorrhizal inoculation response disappeared beyond soil P levels of 25 ppm in Acacia nilotica and 30 ppm in Albizzia lebbeck. Levels of soil P greater than 25 ppm suppressed AM fungus colonization in both species. Soil P levels of 30 and 40 ppm and 40 ppm caused negative mycorrhizal dependencies (MD) in Acacia nilotica and Albizzia lebbeck respectively. Values of MD for both species were negatively correlated with soil P levels. Based on the MD values, regression equations were developed to predict MD for given levels of available P.  相似文献   
57.
Introgression Lines (ILs) carrying alien genomic segments in the homozygous state may or may not be able to contribute positively to the phenotype on account of replacement of cultivated genome segment, however, the genetic elite in heterozygous condition can be attributed to the presence of both recipient and donor genome complements. Therefore, overdominance or pseudo‐overdominance effect at the heterozygous loci is anticipated. Set of 318 ILs, carrying several genomic segments from “A” genome donor wild species, were used for developing test hybrids with CMS line PMS17A. Of these, three hybrids observed significant yield advantage (>25%) over recurrent parents and checks. Parental ILs of these hybrids viz., IL326, IL901 and IL951 carried 5.62%, 2.52% introgression from Oryza rufipogon and 6.71% from Oryza nivara, respectively. These ILs were also crossed with their recurrent parent to develop introgression line hybrids (ILHs) to observe the contribution of the alien segment(s), in the homozygous and heterozygous state. The traits studied have higher mean value when genomic segments from wild species were in the heterozygous state as compared to the homozygous state.  相似文献   
58.
Selection For Flag Leaf Stomatal Frequency In Bread Wheat   总被引:1,自引:0,他引:1  
Two Cultivars Of Bread Wheat (Triticum Aestivum L.) Showing Significant Differences In Stomatal Frequency On The Adaxial Surface Of The Flag Leaf Blade, Were Hybridized. Transgressive Segregation For Stomatal Frequency Was Observed In The F2 Generation and Selections Were Made For High and Low Stomatal Frequency. In The F9 Generation Two Selections Had Significantly Higher Frequencies Than The Higher Parent. Heritability For Stomatal Frequency Based On Parent-Progeny Regression Were 42 % (F3—F4) and 81 % (F4—F5). Stomatal Frequency Was Negatively Correlated With The Flag Leaf Blade Area, Mesophyll Cell Size and Grain Size, However, Exceptions Were Observed.  相似文献   
59.
R. Mitra  C. R. Bhatia 《Euphytica》1982,31(2):429-437
Summary The bioenergetic cost (glucose requirement to provide carbon skeletons and energy production) for the synthesis of 35 chemicals implicated as phytoalexins in combating fungal and bacterial infections as well as the allelochemicals responsible for non-preference or antibiosis in insect-plant interactions were calculated. Heat of combustion values which represent the intrinsic energy content of the molecule for these chemicals, were also computed. The results indicate that the energetic cost of the chemicals responsible for genetic resistance is not exceptionally higher. In fact, they are comparable to those of many fatty acids found in plants. Though the concentration of the chemicals responsible for resistance is low in plant tissues, the total amount per hectare is quite high and consequently the plant resources that go to produce these are high.  相似文献   
60.
Burning of rice straw is a common practice in northwest India, where rice–wheat cropping system is extensively followed. The practice results in loss of nutrients, atmospheric pollution and emission of greenhouse gases. A field experiment was conducted at Indian Agricultural Research Institute, New Delhi, India during the rabi season (November to April) of 2002–2003 to evaluate the efficacy of the various modes of rice straw recycling in soil in improving yield and soil fertility and reducing not only carbon dioxide emission but also nitrous oxide (N2O) emission. The treatment with no rice straw incorporation and application of recommended doses of fertilizer (120, 26 and 50 kg N, P and K ha−1, respectively), gave the highest yield of wheat. Treatments with the incorporation of rice straw at 5 Mg ha−1 with additional amount of inorganic N (60 kg N ha−1) or inoculation of microbial culture had similar grain yields to that of the treatment with no straw incorporation. The lowest yield was recorded in the plots where rice straw was incorporated in soil without additional inorganic N and with manure application. All the treatments with rice straw incorporation had larger soil organic C despite the effect on the mineralisation of soil organic matter. Emission of N2O was more when additional N was added with rice straw and secondary when straw was added to the soil because of higher microbial activity. The study showed that burning of rice straw could be avoided without affecting yield of wheat crop by incorporating rice straw in soil with an additional dose of inorganic N or microbial inoculation. However, the reduction of N2O emission due to avoiding burning is in part counterbalanced by an increase in emission during the subsequent wheat cultivation.  相似文献   
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