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排序方式: 共有353条查询结果,搜索用时 31 毫秒
51.
52.
Lodging-related morphological traits of hybrid rice in a tropical irrigated ecosystem 总被引:1,自引:0,他引:1
M. Sirajul Islam Shaobing Peng Romeo M. Visperas Nelzo Ereful M. Sultan Uddin Bhuiya A.W. Julfiquar 《Field Crops Research》2007
Hybrid rice (Oryza sativa L.) has been proven to be effective in increasing yield potential, but lodging often limits its yield in high-yielding environments. This study was conducted to determine genotypic variation in lodging resistance and lodging-related morphological traits among hybrid and non-hybrid check varieties, and to identify the key morphological traits associated with lodging resistance. Lodging behavior of 16 rice genotypes, including 12 hybrids and four inbreds, was studied at the International Rice Research Institute farm during the 2004 wet season (WS) and 2005 dry season (DS). Grain yield and visual score of lodging were determined at maturity. Lodging-related morphological traits were measured at 30 days after flowering. Large genotypic differences in lodging-related morphological traits were observed. Among these traits, dry weight per unit length, breaking resistance, and lodging index (bending moment/breaking resistance × 100) of lower internodes were significantly correlated with visual score of lodging. Several hybrids demonstrated high lodging resistance although their average plant height was over 120 cm. The lodging-related morphological traits and visual score of lodging in these hybrids were comparable with those of the non-hybrid check varieties with strong lodging resistance. These results suggest that increases in dry weight per unit length and breaking resistance of lower internodes are primary targets for reducing lodging index, thus improving overall lodging resistance of hybrid rice in a breeding program. 相似文献
53.
Bread made from a mixture of wheat and lupin flour possesses a number of health benefits. The addition of lupin flour to wheat flour during breadmaking has major effects on bread properties. The present study investigated the lupin and wheat flour protein interactions during the breadmaking process including dough formation and baking by using proteomics research technologies including MS/MS to identify the proteins. Results revealed that qualitatively most proteins from both lupin and wheat flour remained unchanged after baking as per electrophoretic behavior, whereas some were incorporated into the bread gluten matrix and became unextractable. Most of the lupin α-conglutins could be readily extracted from the lupin-wheat bread even at low salt and nonreducing/nondenaturing extraction conditions. In contrast, most of the β-conglutins lost extractability, suggesting that they were trapped in the bread gluten matrix. The higher thermal stability of α-conglutins compared to β-conglutins is speculated to account for this difference. 相似文献
54.
Fiaz Ahmad Shabab Uddin Niaz Ahmad Rafiq Islam 《Archives of Agronomy and Soil Science》2013,59(3):341-351
The phosphorus-use efficiency of crops in high pH soil is low. A randomized complete block design in a 3 × 2 split-plot experiment was conducted on a high pH silt loam (Typic Ustochrepts) to evaluate whether P-solubilizing microbial (PSM) inocula were able to improve the P fertilization effects on irrigated cotton (Gossypium hirsutum L., cultivar CIM-482). Cotton was planted after seed treatment with PSM inoculation at 0, 22 and 44 kg P ha?1. Results showed that soil microbial populations were significantly higher throughout the cotton-growing season in response to P fertilization and PSM inoculation. Both P fertilization and PSM inocula exerted a significant effect on cotton biomass and Puptake without an interaction. Economic analyses suggest that PSM inocula alone significantly increased P-use efficiency (8%), reduced cost and improved net income (by $36 ha?1) of irrigated cotton production. Moreover, the relationship between relative yield and P fertilization with PSM inocula showed that 95% of the maximum yield of cotton was produced at 22 kg P ha?1, whereas in the absence of PSM inocula, 95% relative yield was obtained at 36 kg P ha?1, asaving of ~39% applied P with PSM inoculation. 相似文献
55.
The present study examines the long-term productivity growth and sustainability of Greek irrigated agriculture. A log linear trend model was used to measure long-term productivity growth, and the total factor productivity (TFP) approach measures the sustainability of the irrigated production system. A time series database of inputs and outputs data were used for the production period of 1961?–?2001 (41 years) which revealed that there is an increasing trend in the irrigated area of the country. The annual growth rate of the irrigated area is 2.6% during this time period. The long-term trends in yields of crops grown in irrigated agriculture are positive. Fertilizer use rate per ha sharply increases during this period. The productivity of irrigated Greek agriculture also increases over the time period as a result of the introduction of High Yielding Variety (HYV), seed, fertilizer and water technology. The measurement of TFP indices indicates that the long-term trend in productivity growth of irrigated Greek agricultural system is positive. The result implies that the irrigated Greek agricultural production system has long-term sustainability. The result also indicates that fertilizer, fixed capital, rainfall and temperature are positively contributing to the mean production of Greek irrigated agriculture. On the other hand, pesticide, labour and fixed capital reduces variability of irrigated agriculture. To this end, long-term agricultural sustainability depends on patterns of input use. 相似文献
56.
M. Robiul Islam Changzhong Ren Zhaohai Zeng Pengfei Jia Egrinya Eneji 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):721-729
Abstract In arid and semiarid regions of northern China, there is an increasing interest in using reduced rates of chemical fertilizer along with water-saving superabsorbent polymer for field crop production. Field experiments were conducted during the year 2009 and 2010 to study the growth performance and yield characteristics of forage oat (Avena sativa L.) as well as soil moisture and nutrient status of the experimental field under different fertilizer (standard, 300; medium, 225; and low, 150 kg ha?1) treatments with (60 kg ha?1) or without application of superabsorbent polymer. Our results show that above-ground biomass accumulation fell by 14.8% under medium and 32.6% under low fertilizer levels whereas application of superabsorbent polymer increased it significantly by 39.7%. Similarly plant height, tiller fertility rate, grain yield, relative water content in the leaves as well as quality of forage also increased for superabsorbent polymer treatment. Considering the trends of growth reduction (qualitative and quantitative) due to fertilizer reduction and progressive influence of superabsorbent polymer on those parameters, it was clear that application of superabsorbent polymer plus only half the conventional fertilizer rate (150 kg ha?1) would be a more appropriate practice for forage oat production under arid and semiarid conditions of northern China or in areas with similar ecologies. 相似文献
57.
Md. Touhidul Islam Baoli Qiu 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):320-325
Abstract Three eggplant (Solanum melongena L.) varieties – ‘Dafeng’, ‘Beisite’, and ‘Baiyu’ – were used in this experiment to discover the least susceptible variety among them to sweetpotato whitefly (Bemisia tabaci) infestation. The investigations were carried out after completing one generation of whitefly based on two points of view. Initially, host preference and suitability of whitefly was investigated based on adult feeding, oviposition, and developmental time. Therefore, it was investigated based on growth responses of eggplant. The average developmental time was shortest for the cohort reared in ‘Dafeng’ (21.3 days), while the longest period (23.2 days) was recorded in ‘Baiyu’. In comparison with the control, less significant changes in the six growth parameters, viz. plant height (12.6%), leaf area (12.7%), dry matter (8.2%), absolute growth rate (26.0%), relative growth rate (25.0%), and net assimilation rate (22.2%) were found in ‘Baiyu’ infested by B. tabaci. Adult attraction and oviposition were reduced while developmental time was increased in ‘Baiyu’ compared with the other two varieties. In addition, the reduction percentages of all the six plant-growth parameters of ‘Baiyu’ were comparatively less than other two varieties to whitefly stress. Our research is focused on a shorter development time; higher feeding, oviposition, and the reduction percentage of plant growth indicate that a plant is a suitable host. In view of this, the present findings indicate that ‘Baiyu’ is less susceptible than the other two varieties, ‘Dafeng’ and ‘Beisite’, for whitefly infestation. 相似文献
58.
Xiao-Fen Jin Dan Liu Ejazul Islam Qaisar Mahmood Xiao-E Yang Zhen-Li He 《Journal of plant nutrition》2013,36(10):1642-1656
ABSTRACT The study demonstrated S. alfredii is an excellent cadmium (Cd)/zinc (Zn) hyperaccumulator as Cd and Zn concentrations in leaves reached 2,183 and 13,799 mg kg?1 DW, respectively. There was a significant increase in root morphological parameters induced by 50 and 500 μM Zn supplement; however, a sharp decrease in these parameters occurred when treated with 100 μM Cd +1000 μM Zn. The inhibited root dehydrogenase activity in 100 μM Cd treated plants was restored to control levels when supplemented with 500 μM Zn. Moderate Zn supplement did not produce significant changes in (malondialdehyde) MDA concentrations as compared with those treated with Cd alone. Variations of the antioxidative enzymes proved an ineffective role in coping with metal-stress in S. alfredii. Combined Cd and Zn treatment significantly enhanced ascorbic acid (AsA) and glutathione (GSH) contents in leaves of S. alfredii, as compared with those treated with Cd alone. Thus, Zn may rely on the involvement of GSH in detoxification and tolerance. 相似文献
59.
This study focused on using quartz porphyry (QP) as a water treatment to improve hydroponic production of komatsuna (Brassica rapa L. nothovar; Japanese mustard spinach). We compared the chemistries of the control and QP-treated nutrient solutions and found that magnesium (Mg2+) and calcium (Ca2+) concentrations increased linearly up to day 21 following sowing in both conditions, then declined slightly. The QP treatment reduced sodium (Na+) and chloride (Cl?) concentrations for the whole cultivation period. In both the control and QP-treated solutions, nitrate (NO? 3) and sulfate (SO2? 4) showed the same trend to a daily increase. In spite of these similarities, however, komatsuna production was better with the QP-treated nutrient solution compared to control. Treatment with QP during cultivation in August–September reduced the harmful effects of Na+, chloride (Cl?), nitrite (NO? 2), and SO2? 4 by reducing concentrations of these ions, possibly leading to decreased salinity and toxicity effects in the plants. Mineral concentrations during October–November differed from those of August/September, resulting in variation among the different growth parameters for komatsuna. 相似文献
60.
Adoption of leaf color chart for nitrogen use efficiency in rice: Impact assessment of a farmer-participatory experiment in West Bengal,India 总被引:1,自引:0,他引:1
Unbalanced and excessive use of N-fertilizers causes environmental pollution, lodging of plants and increased pest pressure, in addition to increased cost to farmers from excessively applied fertilizers and pesticides. N application at the right time and in right amount is critical for healthy plant and environment. Rice leaf color intensity is directly related to leaf chlorophyll content and leaf nitrogen status. The concept for the use of leaf color as an indicator to apply N in rice was crystallized during 1990s. The International Rice Research Institute and the Philippine Rice Research Institute developed a leaf color chart (LCC) that helps guide farmers for real-time nitrogen management in rice farming. The technology is inexpensive, and easily affordable by most resource poor rice farmers. In 2003 we initiated a farmer-participatory research to validate real-time N management in rice by the use of LCC in West Bengal state of India. After 3 years of validation research, a survey was conducted to assess the adoption and impact of LCC. The survey was conducted in both intervention and adjacent control villages and data were collected from 20% farm households selected randomly. In this paper, we report findings of the study on the determinants of adoption of LCC, and its effect on fertilizer and pesticides use. 相似文献