全文获取类型
收费全文 | 118篇 |
免费 | 9篇 |
专业分类
林业 | 5篇 |
农学 | 3篇 |
基础科学 | 2篇 |
29篇 | |
综合类 | 8篇 |
农作物 | 8篇 |
水产渔业 | 12篇 |
畜牧兽医 | 40篇 |
园艺 | 8篇 |
植物保护 | 12篇 |
出版年
2022年 | 6篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 8篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 8篇 |
2009年 | 8篇 |
2008年 | 8篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1970年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有127条查询结果,搜索用时 15 毫秒
1.
Faisal Zulfiqar Suzanne E. Allaire Nudrat Aisha Akram Ana Méndez Adnan Younis Arslan Masood Peerzada 《Journal of plant nutrition》2019,42(11-12):1386-1401
Plant production in potting substrates provides maximum profit on the applied inputs, and hence, directly improving the socio-economic condition of the grower/nurserymen. The main challenge in this industry is sourcing of materials for their potting substrates. Peat and perlite have been widely preferred materials. However, recently higher prices, more restrictive legislation of many countries and wetland ecosystem destruction through its extraction has limited peat use. Nowadays, producers focus towards peat alternatives that provide good performance, are readily available, inexpensive and environment friendly to attain sustainability in potted plant production. In an effort to grasp sustainability during the last few decades, many industrial and agricultural waste materials were reviewed for their use in potting substrates. In these studies, the major focus remained on material characterization, neglecting their economics, technical aspects and environmental impacts. Thus, switching from peat and perlite to alternatives requires material exploration. In the present review, we summarize a clearer and practical approach for substituting different materials especially biochar to fulfill the need of modern potting substrate industry. Biochar has the potential to sustain the substrate production on a long-term basis. 相似文献
2.
Fande Meng Decheng Jin Kai Guo Steven L. Larson John H. Ballard Liangmei Chen Zikri Arslan Guodong Yuan Jeremy R. White Lixiang Zhou Youhua Ma Charles A. Waggoner Fengxiang X. Han 《Water, air, and soil pollution》2018,229(11):369
Anthropogenic activities, such as ore mining and processing, nuclear power generation, and weapon tests, have generated uranium (U) contamination to soils and waters. The mobility and bioavailability of U are influenced by its sources, speciation, and plant species. Phytoremediation has emerged as an environmentally friendly, cost-effective green technology to remediate radioisotope- and metal-contaminated soils. The main objective of this study was to explore the feasibility using sunflower (Helianthus annuus) and Indian mustard (Brassica juncea) in cleaning up soils with UO2, UO3, and UO2(NO3)2. Uranium was found to be bioaccumulated in plant roots more than plant shoots. Uranium uptake by both plant species was significantly higher from the UO3- and uranyl-contaminated soils than from UO2-contaminated soils. UO3- and UO2(NO3)2-contaminated soils showed higher exchangeable, weak acid extractable, and labile U than the UO2-contaminated soils. After a growing season, three U forms decreased as redistribution/transformation of U resulted in U species with lower extractability. This study indicates the importance of U speciation in soil with regard to the potential use of sunflower and Indian mustard for phytoremediation of U-contaminated soils. 相似文献
3.
Nurcan Erbil Zehra Tugba Murathan Mehmet Arslan Ahmet Ilcim Bilge Sayin 《Erwerbs-Obstbau》2018,60(3):203-209
The pear (Pyrus spp.) is one of the most important fruits consumed in daily life. The aim of this study was to determine the total phenolic and ascorbic acid contents, as well as the antimicrobial, antioxidant, and antimutagenic activities, of various pear cultivars. The fruits of five pear (Pyrus communis L.) cultivars (‘Deveci’, ‘Kizil’, ‘Egirsah’, ‘Gugum’, and ‘Banda’) were used in this study. It was determined that the peel and pulp of the ‘Kizil’ pear had the highest total phenolic content (402.5?mg/100?g and 215.2?mg/100?g, respectively), while those of the ‘Banda’ pear had the lowest total phenolic content (326?mg/100?g and 126.1?mg/100?g, respectively). Additionally, the ‘Kizil’ pear showed the highest antioxidant capacity in the 2,2’-azino-bis(3-ethylbenzothiazoline-6-6-sulphonic acid) (ABTS) and ferric-reducing ability assay (FRAP) (1.72 μmol TE/g FW and 161.25?μmol Fe II/g FW, respectively) and the highest ascorbic acid content (16.02?mg/100?g). The ‘Banda’ pear showed the highest antibacterial activity against the test bacteria. However, none of the pear extracts displayed antifungal activity. While all doses of the ‘Kizil’, ‘Gugum’, and ‘Banda’ pear extracts used in this study, except 80?μL/plate, exhibited antimutagenic activities, only the lowest dose (10?μL/plate) of the ‘Deveci’ pear extract showed the antimutagenic activity against induced mutagenesis in the Salmonella typhimurium TA 98 strain. Consequently, the five Turkish pear cultivars used in this study exhibited different levels of antimicrobial, antioxidant, and antimutagenic activities. 相似文献
4.
Kai Guo Steven L. Larson John H. Ballard Zikri Arslan Rong Zhang Yong Ran Yi Su Fengxiang X. Han 《Water, air, and soil pollution》2018,229(4):122
Lead and mercury are two of the most toxic heavy metals in environments. Mesosilicate-templated magnetic nanocarbons with ascorbic acid as carbon precursor were developed through nanocasting processes. The nanocarbon showed effective magnetic separation and the maximum adsorption capacity of 80.6 and 66.3 mg/g for Hg and Pb, respectively. Langmuir model well described adsorption processes of both Hg and Pb from water. Magnetic nanocarbon could be easily separated and incinerated, reducing the volume requiring the disposal. This study indicates that mesosilicate-templated nanocarbons with easy disposal potentials may be good candidates for cleansing Hg and Pb from contaminated water. 相似文献
5.
Sumaira Qutab Rizwan Rasheed M. Arslan Ashraf Iqbal Hussain Nudrat Aisha Akram 《Archives of Agronomy and Soil Science》2017,63(13):1900-1911
The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl2 (0, 50 and 100 µM) and Se (0, 2 and 4 mg L?1) through Hoagland’s nutrient solution. Low Se (2 mg L?1) increased germination percentage and rate, while high Se (4 mg L?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes. 相似文献
6.
Establishment of ornamental and aesthetic plants in hot, arid conditions of India is difficult due to the prevailing climatic, edaphic and biotic factors. Effect of turfgrass on the growth of ornamental plants in hot arid conditions has not been studied so far anywhere in the world. A study was conducted on the campus of Arid Forest Research Institute, Jodhpur, India to assess the performance of a few ornamental plant species in combination with turfgrass and without turfgrass with respect to different soil tilling intervals. Growth of plants was better with turfgrass than without turfgrass. We suggest adopting a soil tilling interval of 30 days to achieve optimum growth of ornamental plant species in terms of height and crown diameter. Our results can help reduce labor costs and achieving better landscapes in fewer days in hot urban conditions of Indian sub continent. 相似文献
7.
Nitrogen mineralisation in soils of various forest sites (pine plantation, natural and thinned oak) at Uluda? University campus in Bursa, Turkey was investigated continuously over a year by the field incubation method. Net nitrogen mineralisation and nitrification rates varied depending on sampling dates. Although nitrogen mineralisation and nitrification rates increased in the spring and summer months, there was no seasonal variation in the soils of the examined forests. Annual net nitrate (NO3?–N) accumulation in the upper soil layer (0–5 cm) was higher in Oak I and Oak II (14 kg ha y?1 and 12 kg ha y?1) than in the pine plantation (8 kg ha y?1). While annual net NO3?–N accumulation (0–5 cm) varied between the oak forests (possibly due to forest management practices), annual net Nmin values were similar in these forests. No significant correlation was found between the examined soil parameters and net nitrification and mineralisation rates in the soils (P > 0.05). These results indicate that tree species and forest management practices play important roles in N cycling in forest ecosystems. 相似文献
8.
9.
Han Chun-yan Chaudhry Maria Tabassum Yao Jia-ying Wang Mi Yang Jia-xin Wang Sheng-nan Zhou Bo Li Yao 《东北农业大学学报(英文版)》2017,24(2)
Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian laying hens were investigated and the possibility of quercetin to decrease cholesterol in eggs and Low Density Lipoprotein cholesterol(LDL-cholesterol) in laying hens were explored. A total of 240 laying hens at 29-week-old were randomly assigned to four treatments, with six replicates of 10 birds per replicate. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g · kg~(-1) quercetin for 8 weeks. Layer performance, lipid concentration in livers, yolks and serum were measured at the end of the experiment. The results showed that laying rate had a quadratic correlation with the level of quercetin(p=0.056) and was maximized by the supplement level of 0.2 g · kg~(-1) diet. When the level of dietary quercetin increased, feed-egg ratio decreased. Crude fat and the total cholesterol of livers decreased by supplementation of quercetin. The total cholesterols of yolks also decreased and had a quadratic correlation with the levels of quercetin(p=0.019). Insulin increased by supplement of quercetin. In conclusion, quercetin improved the performance and reduced egg yolk cholesterol by affecting serum hormone levels. 相似文献
10.
The effects of nitrogen and iron fertilization on growth,yield and fertilizer use efficiency of soybean in a Mediterranean-type soil 总被引:1,自引:0,他引:1
Poor seed yield of soybean in Mediterranean-type environments may result from insufficient iron (Fe) uptake and poor biological nitrogen (N) fixation due to high bicarbonate and pH in soils. This study was conducted to evaluate the effects of N and Fe fertilization on growth and yield of double cropped soybean (cv. SA 88, MG III) in a Mediterranean-type environment in Turkey during 2003 and 2004. The soil of the experimental plots was a Vertisol with 176 g CaCO3 kg−1 and pH 7.7 and 17 g organic matter kg−1 soil. Soybean seeds were inoculated prior to planting with commercial peat inoculants. N fertilizer rates were 0, 40, 80, and 120 kg N ha−1 of which half was applied before planting and the other half at full blooming stage (R2). Fe fertilizer rates were 0, 200 and 400 g Fe EDTA (5.5% Fe and 2% EDTA) ha−1. It was sprayed as two equal portions at two trifoliate (V2) and at five trifoliate stages (V5). Plants were sampled at flower initiation (R1), at full pod (R4) and at full seed (R6) stages. Application of starter N increased biomass and leaf area index at R1 stage whereas Fe fertilization did not affect early growth parameters. N application continued to have a positive effect on growth parameters at later stages and on seed yield. Fe fertilization increased growth parameters at R4 and R6 stages, and final seed yield in both years. This study demonstrated an interactive effect of N and Fe fertilization on growth and yield of soybean in the soil having high bicarbonate and pH. There was a positive interaction between N and Fe at the N rates up to 80 kg N ha−1. However, further increase in N rate produced a negative interaction. Fertilization of soybean with 80 kg N ha−1 and 400 g Fe ha−1 resulted in the highest seed yield in both years. We concluded that application of starter and top dressed N in combination with two split FeEDTA fertilization can be beneficial to improve early growth and final yield of inoculated soybean in Mediterranean-type soils. 相似文献