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81.
Summary Variance analysis is used to measure stability (inter-temporal) and adaptability (over space) components of variance with multilocation-multiyear sorghum yield data from India. Adaptability and stability were highly correlated. Only the stability component is relevant for farmers in their adoption decision. Measures of farmer's risk aversion are used to rank genotypes according to preferences which take account both of yield and stability. Since yield differences were large and risk aversion moderate, preference based rankings did not differ markedly from yield based rankings. 相似文献
82.
On-farm varietal biodiversity was studied through household surveys in two high potential production systems in Chitwan and
Nawalparasi districts of the Nepal Terai and in Lunawada sub-district, Gujarat, India. Diversity was extremely low in Chaite rice in the Nepal study area (weighted diversity 0.04) and low in main season rice in the India study area (weighted diversity
0.34). In both areas, one cultivar dominated, CH 45 in Nepal and GR11 in India. In the India study area, biodiversity varied
with the socio-economic group and better-off farmers had a greater varietal diversity. Participatory varietal selection (PVS)
identified new varieties that farmers preferred. Their adoption by farmers increased on-farm varietal biodiversity within
the three cropping seasons studied. Despite the commonly assumed uniformity of high potential production systems, the new
varieties occupied specific niches in the farming system. Farmers' preferences for different varieties – there were large
differences in quality traits and maturity period among the new varieties – should help to maintain biodiversity. Overall
production is expected to increase as each niche becomes occupied increasingly by the best-adapted variety. PVS is a simple
and powerful method of increasing food production in the high potential production systems that produce most of the developing
world's grain.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
83.
Sharma Umesh Bhardwaj Daulat Ram Sharma Sunny Sankhyan Neeraj Thakur Chaman Lal Rana Neerja Sharma Subhash 《Agroforestry Systems》2022,96(5-6):925-940
Agroforestry Systems - Agroforestry as a smart agriculture practice has started to get global attention nowadays. The present investigation is based on bamboo-ginger intercropping research carried... 相似文献
84.
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86.
Some of the factors influencing the propagation of caper (Capparis spinosa L.) plants in vitro and germination of the seed were studied. The number of adventitious shoots emerging from caper stems cultured in vitro increased from 2.2 shoots per explant when the growth medium contained 2 mg/L of gibberellic acid (GA3) to 5.5 when the growth medium contained 2 mg/L zeatin riboside (ZR) and 1 mg/L naphthalene acetic acid (NAA). The best medium for callus formation from leaf and stem parts contained the growth regulators 1 mg/L 6-benzylaminopurine (BAP) and 0.1 mg/L NAA and the best medium for plant regeneration contained 1 mg/L kinetin and 0.1 mg/L indole-3-acetic acid (IAA). The effect of gamma irradiation on the growth of caper shoots in vitro was also studied. A 10 Gy dose of gamma irradiation stimulated growth of shoots up to 200% and increased shoot rooting percentage from 75 to 100%. 相似文献
87.
Influence of socio-economic and cultural factors in rice varietal diversity management on-farm in Nepal 总被引:1,自引:0,他引:1
Ram Bahadur Rana Chris Garforth Bhuwon Sthapit Devra Jarvis 《Agriculture and Human Values》2007,24(4):461-472
A questionnaire survey of 408 households explored the role of socio-economic and cultural factors in rice (Oryza sativa L.) varietal diversity management on-farm in two contrasting eco-sites in Nepal. Multiple regression outputs suggest that
number of parcels of land, livestock number, number of rice ecosystems, agro-ecology (altitude), and use of chemical fertilizer
have a significant positive influence on landrace diversity on-farm, while membership in farmers’ groups linked to extension
services has significant but negative influence on landrace diversity. Factors with significant positive influence on diversity
of modern varieties on-farm were number of parcels of land and of rice ecosystems, access to irrigation, membership in farmers’
groups, and use of insecticide. Within communities, resource-endowed households maintain significantly higher varietal diversity
on-farm than resource-poor households and play a significant role in conserving landraces that are vulnerable to genetic erosion
and those with socio-cultural and market-preferred traits. Resource-poor households also contribute to local diversity conservation
but at lower richness and area coverage levels than resource-endowed households. Households where a female had assumed the
role of head of household due to death or migrant work of her husband had less diversity due to lower labor availability.
Landraces with socio-cultural and market-preferred traits are few in number but have potential to be conserved on-farm.
相似文献
Ram Bahadur RanaEmail: |
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89.
Mubshar Hussain Rana Qaisar Abbas Muhammad Faizan Ashraf Muhammad Shahzad Muhammad Farooq 《Journal of plant nutrition》2013,36(18):2330-2343
AbstractNitrogen use efficiency (NUE) is low in cereals especially in wheat. Different wheat cultivars may vary in NUE due to inherited biological nitrification inhibition (BNI) potential. In this study, three wheat cultivars (Punjab-2011, ARRI-2011 and Millat-2011) were fertilized at the rate of 140?kg ha?1 with three N sources [nitrophos (NP), urea and calcium ammonium nitrate (CAN)]. The soil nitrate (NO3?)-N contents were significantly enhanced coupled with simultaneous decrease in ammonium (NH4+)-N contents in the rhizosphere of cultivar Punjab-2011, fertilized with NP; however, cultivar Millat-2011 receiving urea behaved in contrast. Wheat cultivar Punjab-2011 fertilized with NP had the highest grain yield and agronomic NUE than other treatments due to significant increase in chlorophyl contents, allometric and yield parameters. The highest net benefit was recorded from the cultivar Punjab-2011 fertilized with CAN. In conclusion, use of NP in Punjab-2011 enhanced the grain yield and agronomic NUE. 相似文献
90.
Daizy R. Batish Harminder P. Singh Nipunika Rana Ravinder K. Kohli 《Archives of Agronomy and Soil Science》2013,59(6):705-715
Abstract A study conducted to assess the allelopathic interference of invasive weed Chenopodium album indicated that aqueous leachates of C. album plant parts (roots, whole plant, and leaves), debris extracts and rhizosphere soil deleteriously affected the germination and initial growth of two test plants – Cassia occidentalis (a weed) and Phaseolus aureus (a crop). Further, the plant growth in terms of height, biomass, chlorophyll and protein content was significantly lesser in soil amended with C. album debris. Aqueous leachates, debris extracts, rhizosphere soil and debris amended soil were found to contain significantly higher amounts of water-soluble phenolics – the known phytotoxins. These phytotoxins in root, above-ground parts and leaves were phenolic acids, namely gallic, chlorogenic, caffeic, vanillic, p-coumaric, syringic and ferulic. Among these, chlorogenic acid was present in the maximum amount in the leaves and roots. The study concludes that C. album releases phenolics into the soil and these are probably involved in the growth inhibitory effect of C. album. 相似文献