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971.
分别选用复合磷酸盐、卡拉胶、玉米淀粉、蛋清作为添加物,进行其对青鱼鱼丸品质影响的研究。结果表明各添加物最适添加量分别为:w(复合磷酸盐)=0.5%,w(卡拉胶)=0.3%,w(玉米淀粉)=15%,w(蛋清)=3%。 相似文献
972.
采用PKO无机培养基,从地八角根际分离具有溶磷能力的菌株,通过溶磷圈法筛选出7株解磷能力较强的菌株进行深入研究。利用钼蓝比色法对菌株在液体培养条件下的溶磷能力进行测定,结果表明:筛选的菌株分解磷酸钙的能力差异不大,溶磷量在123.37~135.23μg/mL之间,各菌株的溶磷量与分泌有机酸量、培养介质pH值之间均不存在显著相关性;各菌株均具有分泌IAA能力,大多数菌落呈淡黄色或乳白色、不规则、不透明、扁平、无色素;除1株菌表现为中性外,其他6株表现为产碱性;所有菌株在以甘露醇、蔗糖、1/2甘露醇+1/2蔗糖、葡萄糖、木糖、麦芽糖取代蛋白胨的碳源培养基上均生长良好。其中,DBR2菌株经16SrDNA序列分析,初步鉴定为肠杆菌。 相似文献
973.
选用不同浓度的KH2PO4分别对盆栽金盏菊进行了叶面喷肥试验。结果表明:2‰KH2PO4不仅可促进金盏菊幼苗生长,还可提旱花期,提高花的产量及品质,增加叶绿素含量,能满足金盏菊生长对养分的长期需求,即磷钾肥更适于盆栽金盏菊的生长发育。 相似文献
974.
975.
976.
[目的]探究最优的磁效应参数,提高砖红壤中磷素吸收率。[方法]通过连续培养的方法,以未经磁场处理的土样作对照,测定不同磁化强度对砖红壤中无机磷细菌和有机磷细菌的影响。[结果]在整个磁处理过程中,对2种溶磷细菌影响最大的是500 mT处理第3天。在整个磁处理过程中,100 mT对2种磷细菌表现为抑制作用,但与CK相比基本达不到显著水平。300、500和700 mT对2种磷细菌均表现为促进作用。磁处理对2种磷细菌产生的影响存在不同程度的滞后及衰退效果。[结论]磁处理对溶磷细菌的生长影响较大,可用于快速获得大量的溶磷细菌。 相似文献
977.
Can phosphorus fertilizers sparingly soluble in water decrease phosphorus leaching loss from an acid peat soil?
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The potential risk of phosphorus (P) loss in surface run‐off can be decreased using sparingly soluble forms of P fertilizer (e.g. reactive phosphate rock (RPR)). However, it is unclear whether RPR can decrease P loss in leachate, especially when applied to soils with a small anion storage capacity (viz. P sorption capacity) and pH. Our hypothesis was that at low soil pH, the solubility of RPR would increase and result in P losses in leachate similar to those receiving single superphosphate (SSP), but at higher pH, less P would be lost from soils receiving RPR than SSP. Lysimeters containing a crushed, sieved acid mesic Organic (viz. peat) subsoil (30–60 cm) were limed to pH 4.5, 5.5 or 6.5 and treated with SSP or RPR at rates of 0, 50, 100 or 200 kg P/ha. Lysimeters were sown with ryegrass and watered over 12 months under controlled conditions and the leachate collected. Losses of filtered (< 0.45 μm) reactive inorganic P (FRP) and unreactive or organic P (FUP) in leachate were greatest for pH 4.5 treatments and least for the pH 6.5 treatments. The difference in FRP and FUP leachate losses in RPR‐ and SSP‐treated soils was smaller at pH 4.5 and 5.5, and increased at pH 6.5 as losses from soils receiving RPR decreased compared to those receiving SSP. The results suggest that RPR can be used as a strategy to decrease P losses in leachate from an acid Organic soil with small P sorption capacity when limed to > pH 5.5. 相似文献
978.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):25-39
Abstract Accurate measurement and characterization of phosphate rock dissolution are important for a better understanding of phosphorus (P) availability in soils. An incubation study was carried out on two New Zealand topsoils (0–15 cm; high P buffering capacity Craigieburn and low P buffering capacity Templeton) amended with North Carolina phosphate rock (NCPR) and water‐soluble phosphate (WSP) at 218 mg P kg?1 (equivalent to 60 kg P ha?1). Isotopic exchange kinetics was carried out after 12 h and 28 days of incubation to characterize P availability. This study showed that sensitivity of capacity factors (r1/R, n) to explain changes in E1min values was affected by the P buffering capacity of the soils. The recovery of applied P in the E pool (RecinE%) with extended incubation time was similar from the NCPR and WSP treatments (3.1–3.3%) in the Craigieburn soil compared with the Templeton soil in which RecinE% values were greater in WSP (9%) than NCPR (1.3%) treatment. The higher values of P derived from the applied P fertilizers in the E pool (PdffinE%>80%) suggested that the NCPR application in both soils would be efficient for increasing P availability to plants. 相似文献
979.
L. Jordan‐Meille G. H. Rubæk P. A. I. Ehlert V. Genot G. Hofman K. Goulding J. Recknagel G. Provolo P. Barraclough 《Soil Use and Management》2012,28(4):419-435
The procedure for applying phosphorus (P) fertilizer to soil can be divided into three consecutive steps: (i) Measurement of soil‐P availability, (ii) calibration of the soil‐P fertility level and (iii) estimation of the recommended P dose. Information on each of these steps was obtained for 18 European countries and regions with the aim of comparing P fertilizer recommendation systems at the European scale. We collected information on P fertilizer recommendations through conventional or grey literature, and personal contacts with researchers, laboratories and advisory services. We found much variation between countries for each of the three steps: There are more than 10 soil‐P tests currently in use, apparent contradictions in the interpretation of soil‐P test values and more than 3‐fold differences in the P fertilizer recommendations for similar soil‐crop situations. This last result was confirmed by conducting a simple experimental inter‐laboratory comparison. Moreover, soil properties (pH, clay content) and crop species characteristics (P responsiveness) are used in some countries in the calibration and recommendation steps, but in different ways. However, there are also common characteristics: soil‐P availability is determined in all countries by extraction with chemical reagents and the calibration of the soil‐P test values, and the fertilizer recommendations are based on the results from empirical field trials. Moreover, the fertilizer recommendations are nearly all based on the amount of P exported in the crops. As long as rational scientific and theoretical backgrounds are lacking, there is no point in trying to synchronize the different chemical methods used. We therefore call for a mechanistic approach in which the processes involved in plant P nutrition are truly reproduced by a single standard method or simulated by sorption‐desorption models. 相似文献
980.
WANG Hong-yuan LIU Shen ZHAI Li-mei ZHANG Ji-zong REN Tian-zhi FAN Bing-quan LIU Hong-bin 《中国农业科学(英文版)》2015,(1):158-167
In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus(PSF). This strain generated 689 mg soluble P L–1 NBRIP medium after 10 d of culture. To produce an affordable biofertilizer using A. niger 1107, the potential of widely available carrier materials for growth and maintenance of this strain were evaluated. The effects of sterilization procedures(autoclaving and gamma-ray irradiation) on the suitability of these carriers to maintain growth of the fungus were also investigated. The carrier materials were peat, corn cobs with 20%(w/w) perlite(CCP), wheat husks with 20%(w/w) perlite(WHP), and composted cattle manure with 20%(w/w) perlite(CCMP). In the first 5-6 mon of storage, the carriers sterilized by gamma-ray irradiation maintained higher inoculum loads than those in carriers sterilized by autoclaving. However, this effect was not detectable after 7 mon of storage. For the P-biofertilizer on WHP, more than 2.0×107 viable spores of A. niger g–1 inoculant survived after 7 mon of storage. When this biofertilizer was applied to Chinese cabbage in a pot experiment, there were 5.6×106 spores of A. niger g–1 soil before plant harvesting. In the pot experiment, Chinese cabbage plants grown in soil treated with peat- and WHP-based P-biofertilizers showed significantly greater growth(P<0.05) than that of plants grown in soil treated with free-cell biofertilizer or the CCMP-based biofertilizer. Also, the peat- and WHP-based P-biofertilizers increased the available P content in soil. 相似文献