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121.
122.
施磷肥对红小豆吸磷及产量的影响 总被引:1,自引:0,他引:1
试验研究了潮土区不同施P肥量对红小豆含P量及产量的影响。结果表明,在土壤有效磷含量为9mg/kg条件下P肥对红小豆增产效果达极显著水平,施纯P 68.8kg/hm2时产量最高。红小豆全生育期含P量呈单峰曲线,花后10 d左右达最大。结荚鼓粒期及成熟期含P量与产量呈显著正相关关系,相关系数分别为0.9375和0.7863。各生育阶段的适宜含P量始花前为4.0mg/g,始花期至花后20 d为4.4~4.8mg/g,花后20 d后为3.9~3.5mg/g。产量(Y)与吸P量(x)间的关系为二次曲线,其决定系数为0.9823,施P量与吸P量间呈极显著正相关关系,相关系数为0.9644。 相似文献
123.
124.
红壤稻田施用磷矿粉和硫磺对油菜产量和养分吸收的影响结果表明:单施突尼斯Gafsa磷矿粉、中国昆阳磷矿粉和普钙处理油菜分别比对照增产22.2~23.2倍、13.7~13.9倍和21.2倍,硫磺与磷矿粉混施进一步提高了磷矿粉的增产作用;昆阳磷矿粉、Gafsa磷矿粉和普钙各处理P总吸收量分别比对照提高6.7倍、15.8倍和13.8倍,硫磺与昆阳磷矿粉和Gafsa磷矿粉配施分别使油菜P总吸收量提高69.2%和11.4%;单施磷矿粉处理或磷矿粉与硫磺混施处理增加了油菜收获时土壤有效硫含量,但未增加土壤速效磷含量。 相似文献
125.
应用XPS技术研究了不同pH条件下针铁矿表面磷的配位形式及转化特点。结果表明:磷浓度-定时,低pH值有利于形成克的单基配位,高pH值有利于形成磷的双基配位。体系p值升高,针铁矿表面的单基配位磷即较快地向双基配位磷转化;pH降低,双基配位磷则缓慢地向单基配位磷转化。分析认为,体系pH通过影响溶液中磷酸根的离子类型来影响针铁矿表面吸附磷的配位形式,pH变化引起表面磷酸根系子的解离和缔合,是导致针铁矿表 相似文献
126.
The objective of the present work was to examine the effects of phosphate fertilizers on the microbial activity of pasture soils. Various microbial characteristics were measured using soils from an existing long-term phosphate fertilizer field trial and a short-term incubation experiment. The measurements included basal respiration, substrate induced respiration, inhibition of substrate-induced respiration by streptomycin sulphate (fungal activity) and actidione (bacterial activity) and microbial biomass C. The long-term field trials was initiated during 1985 to examine the effectiveness of different sources of phosphate fertilizers (single superphosphate, North Carolina phosphate rock, partially acidulated North Carolina phosphate rock, and diammonium phosphate) on pasture yield. The incubation experiment was conducted for 8 weeks using the same soil and the sources of phosphate fertilizers used in the field trial. In the incubation experiment the fertilizer addition caused an initial decrease in basal and substrate-induced respiration but had no effect on total microbial biomass. The initial decline in basal and substrate-induced respiration with the fertilizer addition was restored within 8 weeks after incubation. In the field experiment the fertilizer addtion had no significant effect on basal respiration but increased substrate-induced respiration and microbial biomass C. The short-term and the long-term effects of phosphate fertilizer addition on the microbial characteristies of the soils are discussed in relation to its effects on pH, salt concentration, and the nutrient status of the soils. 相似文献
127.
Organic resources and earthworms affect phosphorus availability to sorghum after phosphate rock addition in semi-arid West Africa 总被引:1,自引:0,他引:1
Elisée Ouédraogo Lijbert Brussaard Abdoulaye Mando Leo Stroosnijder 《Biology and Fertility of Soils》2005,41(6):458-465
A field experiment was laid out in Burkina Faso (West Africa) on an Eutric Cambisol to investigate the interaction of organic resource quality and phosphate rock on crop yield and to assess the contribution of earthworms (Millsonia inermis Michaelsen) to P availability after phosphate rock application. Organic resources of different quality were applied at a dose equivalent to 40 kg N ha–1 with or without phosphate rock from Kodjari (Burkina Faso) at a dose equivalent to 25 kg P ha–1, and were compared with control and single phosphate rock treatments in a factorial complete block design with four replicates. Sorghum (Sorghum bicolor L. Moench) variety SARIASSO 14 was grown. Sheep dung had the highest impact on earthworm casting intensity followed by maize straw. Combining organic resources with phosphate rock reduced earthworm casting activities compared to a single application of organic resources or phosphate rock. Addition of phosphate rock to maize straw reduced P availability in earthworm casts whereas combining sheep dung or compost with phosphate rock increased P availability. The contribution of earthworms to Kodjari phosphate rock solubilisation mainly occurred through their casts, as the available P content of casts was 4 times higher than that of the surrounding soil. 相似文献
128.
目的:研究有机肥和磷肥不同梯度施肥水平对直缘乌头产量的影响。方法:采用单因素随机设计研究有机肥和磷肥对直缘乌头块根商品产量、苗块根产量及总产量的影响。结果:直缘乌头商品块根产量与有机肥施用量呈正相关关系,有机肥施用量高于2 00kg/667m2对苗块根的产生没有显著差异,在中等以下的土壤肥力条件下,有机肥最佳施用量为3 00kg/667m2。直缘乌头栽培对磷肥较为敏感,过量磷肥易对商品块根的生长可产生肥害,磷肥最佳施用量为30kg/667m2。结论:施用适量的有机肥和磷肥可显著提高直缘乌头产量。 相似文献
129.
不同类型土壤对大豆磷肥利用率影响的研究 总被引:7,自引:0,他引:7
试验选用黑土、草甸土、白浆土等类型土壤进行盆栽试验,研究了大豆在不同类型土壤中常规施肥的磷肥利用率;通过采用氨磷钾最佳比例及用量与叶面喷施液体肥料相结合的方法,使大豆磷肥利用率与常规化肥用量相比在黑土中提高6.25个百分点;在草甸土中提高5.12个百分点;在白浆土中提高5.86个百分点。大豆产量与常规化肥用量相比,分别在黑土、草甸土、白浆土中增产6.73%、9.56%、7.69%。 相似文献
130.
Munees AhemadMohammad Saghir Khan 《Pesticide biochemistry and physiology》2011,100(1):51-56
In this study, four technical grade insecticides, fipronil, pyriproxyfen, imidacloprid and thiamethoxam were applied at the recommended and the higher doses to investigate their effects on plant growth-promoting activities of phosphate-solubilizing Klebsiella sp. strain PS19, isolated from mustard rhizosphere. All tested insecticides displayed a concentration-dependent inhibition in plant growth promoting traits, like, inorganic phosphate solubilization, biosynthesis of phytohormones and siderophores, of rhizobacterial strain PS19. For example, the phosphate-solubilizing activity of Klebsiella sp. PS 19 was reduced maximally by 95%, at 3900 μg l−1 pyriproxyfen over control. At the recommended rate, the magnitude of toxicity of insecticides to plant growth promoting traits was less severe compared to the higher doses. The sequence of insecticide-toxicity expressed as percent decrease, determined at highest dose rate of each insecticide, over control was: pyriproxyfen (95) = imidacloprid (95) > thiamethoxam (94) > fipronil (85), for phosphate-solubilizing activity while for salicylic acid (SA) it was: thiamethoxam > pyriproxyfen = imidacloprid > fipronil. The impact of the highest dose rate of insecticides on 2,3-dihydroxybenzoic acid (DHBA) was almost equal to those observed for SA. Thiamethoxam decreased the indole acetic acid (IAA) synthesis maximally by 86% whereas fipronil had least toxicity and reduced it by 67% relative to the control. Among the experimental insecticides, pyriproxyfen at 3900 μg l−1 in general, had the greatest toxic effects for plant growth promoting activities of the test strain. The study inferred that insecticides affect the plant beneficial activities of rhizobacteria adversely. These findings are likely to add a new insight into the pest management practices. 相似文献