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21.
In Israel four European pear cultivars are grown: ‘Spadona’ is the main cultivar and ‘Coscia’, ‘Gentile’ and ‘Spadochina’ are its pollinators. However, molecular S-genotyping revealed that ‘Spadona’ is semi-compatible with its three pollinators. This explains, at least in part, the relatively low pear yield in Israel. The Syrian pear (Pyrus syriaca) grows wild in Israel and blooms intensively, overlapping the blooming of the cultivated European pears. Cross-fertilization between Syrian pear and ‘Spadona’ was shown to be efficient suggesting that Syrian pear might be a potent pollinator for ‘Spadona’. Twenty-six Syrian pear seedlings, from different sites in north-east Israel were S-genotyped identifying 11 that are fully compatible with the four European pear varieties cultivated in Israel. By this screening, 24 different S-RNases were cloned; ten of them are new, whereas the other fourteen had been identified previously. In addition, seedlings of two wild pear species were also S-genotyped. Two seedlings from Pyrus betulifolia and one from Pyrus korshinskii were found to be genetically compatible with the four European pear cultivars. From these seedlings four S-RNases were cloned, two are new, one had been cloned previously and one was identical to an S-RNase allele cloned from Syrian pear in this work.  相似文献   
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Although the second largest chromosome of the genome, the X chromosome is usually excluded from genome-wide association studies (GWAS). Considering the presence and importance of genes on this chromosome that are involved in reproduction, the aim of this study was to evaluate the effect of its inclusion in GWAS on reproductive traits (scrotal circumference [SC], early pregnancy [P16] and age at first calving [AFC]) in a Nelore herd. Genotype data from 3,263 animals with the above-mentioned phenotypes were used. The results showed an increase in the variances explained by the autosomal markers for all traits when the X chromosome was not included. For SC, there was an increase of more than 10% for the windows on chromosomes 2 and 6. For P16, the effect was increased by almost 20% for windows on chromosome 5. The same pattern was found for AFC, with an increase of more than 10% for the most important windows. The results indicate that the noninclusion of the X chromosome can overestimate the effects of autosomes on SC, P16 and AFC not only because of the additive effect of the X chromosome itself but also because of its epistatic effect on autosomal genes.  相似文献   
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Leaching of sulfur (S) on sandy soils may limit the effectiveness of S fertilizers especially when applied at sowing. The effectiveness of S sources for canola (oil seed rape, Brassica napus L.) grown in sandy low S soils of south-western Australia is not known. This study was completed to determine the relative effectiveness of gypsum and a gypsum-based by-product from synthetic rutile processing called Canola Blue for canola grown in low S soils of the region. Canola Blue is a mixture of gypsum and elemental S, and is granulated so its effectiveness may vary from gypsum. We measured the effectiveness of the two S sources in the glasshouse for young seedling growth and for minimizing S leaching. In the four field experiments, the two S sources were evaluated for relative effects on canola seed yield and the concentration of oil in seed. Canola Blue applied at sowing was as effective as gypsum for canola growth in the glasshouse and when applied at 35 days after sowing (DAS) was as effective as gypsum for seed yield in the field. For the glasshouse study, Canola Blue when applied to the soil surface (topdressed) at 35 DAS was as effective as gypsum in achieving a rapid recovery of leaves from S deficiency symptoms and of shoot growth. Where S deficiency appears during the growing season, topdressing with Canola Blue appears to be as effective under the conditions of this experiment as was gypsum. However, the S in Canola Blue was less prone to leaching than that applied as gypsum.  相似文献   
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Background  

Mopane (Colophospermum mopane) plants form monotypic woodlands that cover extensive areas in northern Botswana. Mopane is also a principal food item in the diet of elephants. Obtrusive damage to mopane plants as a result of elephant feeding may alter the structure of mopane woodlands. Some mopane woodland areas in northern Botswana are subjected to heavy elephant utilization rates whereas other mopane areas are less affected. However, the underlying reason for the concentrated elephant utilization is unknown.  相似文献   
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A survey identified viruses infecting garlic, leek and onion crops and wild Allium species in Greece. Virus identification was based on ELISA, immunoelectron microscopy, and occasionally on RT-PCR. Samples of cultivated Allium species were collected from five districts, whereas samples of twenty-seven wild Allium species were also collected from all over Greece. Onion yellow dwarf virus (OYDV) and Leek yellow stripe virus (LYSV) were identified in 98.5% and 83.7% of all samples, respectively, and were found in all regions. Allexiviruses were also detected in all regions and their incidence ranged from 62.5% to 70.5% (depending on region and type of allexivirus). Garlic common latent virus (GCLV) was detected in samples from Arcadia (97.6%) and Evia (18.0%) and in one field in Larissa (23.0%). Shallot latent virus (SLV) was found only in two areas (Evros and Theva) and in fields planted with imported propagative material, from Iran and China. The incidence of virus-like symptoms in leek crops ranged from 10.0% to 90.0% in different regions and fields and all symptomatic plants were found to be infected by LYSV. Onion yellow dwarf virus was only found in seven symptomatic onion samples from southern Greece. Allium ampeloprasum spp. ampeloprasum and Allium flavum, were the only wild Allium species found to be infected with LYSV. Finally Turnip mosaic virus (TuMV) was found in A. sphaerocephalon, A. guttatum, A. subhirsutum, and A. neapolitanum.  相似文献   
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Desmitis of the origin of the suspensory ligament is a common injury of sport horses; however, it remains a diagnostic challenge. The anatomy of the region can lead to difficulties localising the lameness. Diagnostic imaging may be complicated by overlying structures and the limitations of the imaging modalities readily available. A logical approach to clinical examination, diagnostic analgesia and multimodal imaging can help to overcome these difficulties.  相似文献   
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