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111.
Summary Nineteen isolates of Melampsora medusae (Thüm.), collected from natural stands of Populus deltoides (Bartr.) along the lower Mississipi River Valley, were tested for the occurrence of physiologic races by inoculation of nine poplar clones. Eight distinct races were identified based upon differential responses on these clones. However, most of the isolates also differed in their aggressiveness (latent period and uredial number per leaf disk), and a significant isolate × cultivar interaction was observed for both traits. Within a specific geographic location, more than one race was present. Isolates from the northernmost sampling location (37°N latitude) appeared more aggressive than those from southern latitudes (34–36°N latitude). Thus wild pathosystems may be composed of variable pathogen populations differing in virulence and the apparent stability usually observed in such systems may be due to the genetic diversity of the host population in interaction with many epidemiological and ecological factors.The investigation reported in this paper (No. 86-8-96) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with approval of the Director. 相似文献
112.
Summary The influence of cytoplasmic differences on shoot regeneration response has been investigated inB. carinata (BBCC) synthesised from reciprocal crosses betweenB. nigra (BB) andB. oleracea (CC). Mean shoot regeneration response from cotyledons of C cytoplasmic origin was twice as high as that from cotyledons with B cytoplasm. Statistical analysis of data indicated significant differences between cytoplasms, among growth regulator combinations and between cytoplasms and growth regulator interactions 相似文献
113.
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
114.
Development of a New Cytoplasmic Male-Sterility System in Brassica juncea through Wide Hybridization
A new cytoplasmic male-sterility system was developed in an oilseed Brassica, viz. B. juncea var. ‘Pusa Bold’ with the cytoplasmic background of a wild species, Diplotaxis siifolia, obtained through wide hybridization. The synthetic alloploid (D. siifolia×B. juncea: 2n = 56, D3D3AABB) was repeatedly backcrossed to B. juncea to achieve cytoplasmic substitution. The CMS plants resembled the cultivar in growth and morphology. The flowers had narrow sepals and petals and short, shrivelled anthers which failed to dehisce. The meiotic process appeared to be normal. The microspores degenerated at an early stage after tetrad formation. Female fertility in the CMS plants was as good as in the cultivar. Female transmission of sterility confirmed it to be cytoplasmically encoded. 相似文献
115.
Simple sequence repeat markers for botanical varieties of cultivated peanut (Arachis hypogaea L.) 总被引:1,自引:0,他引:1
Guohao He Ronghua Meng Hui Gao Baozhu Guo Guoqing Gao Melanie Newman Roy N Pittman C. S. Prakash 《Euphytica》2005,142(1-2):131-136
Cultivated peanut (Arachis hypogaea L.) consists of six botanical varieties. Identification of DNA markers associated with botanical varieties would be useful in plant genotyping, germplasm management, and evolutionary studies. We have developed 130 simple sequence repeat (SSR) markers in peanut, 38 of which were used in this study because of their ability in detecting genetic polymorphism among 24 peanut accessions. Eight SSR markers were found useful to classify botanical varieties. Among them, six SSR markers were specific to botanical varieties fastigiata and vulgaris, one to botanical varieties hypogaea and hirsuta, and one to botanical varieties peruviana, and aequatoriana. Also, three of them derived from peanut expressed sequence tags (ESTs) were associated with putative genes. As botanical varieties have different morphological traits and belong to different subspecies in A. hypogaea, these markers might be associated with genes involved in the expression of morphological traits. The results also suggested that SSRs (also called microsatellites) might play a role in shaping evolution of cultivated peanut. Multiplex PCR of botanical variety-specific markers could be applied to facilitate efficient genotyping of the peanut lines. 相似文献
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Shah Mudasir Ahmad Kumar Rohit Kinjavdekar Prakash Amarpal Aithal H. P. Arif Basha Mohammad Majid Asif 《Veterinary research communications》2022,46(2):563-575
Veterinary Research Communications - A prospective clinical study consisting of six bovines (200–300 kg body weight) undergoing open tibial fractures was carried out, to evaluate the... 相似文献
120.
Anirban Biswas Saroni Biswas Rama Venkata Srikanth Lavu Prakash Chandra Gupta Subhas Chandra Santra 《Paddy and Water Environment》2014,12(3):379-386
Rice is prone to arsenic accumulation compared to other cereals as typically grown up under waterlogged situation favoring arsenic mobility. Arsenic in rice depends on arsenic availability to plants from irrigation water, even differs among cultivars and their plant parts. Present study was concentrated on arsenic accumulation in various plant parts of five common rice cultivars grown using irrigation water from different water sources in various fields in arsenic-endemic region. Additionally, dose response experiment under laboratory net house was conducted on the same cultivars excluding open environmental factors. The common cultivars were categorized according to high to low arsenic accumulator in rice grain, straw and root parts. The cultivar Shatabdi has shown highest arsenic accumulation in rice grain compared to other rice cultivars in fields and when grown at various soil arsenic doses. In field samples, a highest grain arsenic concentration ranged between 0.69 ± 0.04 and 0.78 ± 0.12 mg kg?1 for Shatabdi, whereas lowest grain arsenic concentration ranged between 0.37 ± 0.07 and 0.41 ± 0.07 mg kg?1 for the cultivars GB3 and Lalat. Speciation study detected more inorganic arsenic than organoarsenicals with a trend of arsenite > arsenate > DMA > MMA, which would be problem for consumers. The concluding remark is the characterization of common rice cultivars according to arsenic concentration to highlight an important remediation strand by changing to low arsenic cultivar. 相似文献