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21.
通过田间试验,研究了氮、磷、钾肥料施用量对水稻产量及植株性状的影响,结果表明,氮、磷、钾肥施用均可提高水稻产量,氮肥是增产的主要因子,远高于磷、钾肥增产效果。产量(y)与施氮量(x1)、施磷量(x2)、施钾量(x3)呈抛物线关系,其回归方程分别为:y=-0.021 9x12+18.255x1+5 063.8;y=-0.135 3x22+29.049x2+7 159.4;y=-0.033 7x32+15.238x3+7 057.2。不同肥料因子对水稻产量构成影响不一,氮肥促进有效穗数、穗粒数增加,而降低千粒重;磷肥促进有效穗数、千粒重增加,而对穗粒数影响不大;钾肥促进穗粒数、千粒重增加,而对有效穗数影响不大。氮、磷、钾肥对水稻形态影响不一,3种肥料因子均能增加叶面积,但氮肥增加幅度显著高于磷肥和钾肥;氮肥增加株高和穗长显著,而磷钾肥效果不显著。 相似文献
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S. Gupta R. Kaushal R. S. Spehia S. S. Pathania V. Sharma 《Journal of plant nutrition》2017,40(7):921-927
Inorganic fertilizers alone cannot sustain high levels of productivity. This study was conducted to determine whether higher productivity of capsicum could be achieved by conjoint application of chemical fertilizers and plant growth promoting rhizobacteria (PGPR). Four PGPR isolates (RS2, RS3, RS4, and RS7) from capsicum roots and rhizosphere were evaluated at Solan, Himachal Pradesh (India), during 2009–2012. Two best performers: RS2 and RS7 were tried singly or in consortium with different levels of chemical fertilizers under field conditions, Randomized Block Design, replicated thrice. The conjoint use of 100% recommended nitrogen, phosphorus, and potassium (NPK) doses through chemical fertilizers (RDF) plus PGPR significantly increased fruit yield, plant height, and biomass by 37%, 20%, and 30%, respectively, over sole application of 100% RDF (control). Further, response of capsicum to 80% RDF plus PGPR was statistically comparable with control. The results, therefore, indicate the potential of isolated PGPR strains to substitute about 20% NP fertilizers besides enhanced productivity of capsicum. 相似文献
24.
基于均匀设计研究氮、磷、钾肥对马铃薯产量的影响 总被引:1,自引:0,他引:1
运用均匀设计法研究不同氮、磷、钾配施对马铃薯产量的影响。以马铃薯品种尤金为供试材料,在田间条件下以氮、磷、钾施用量和配比作为变量,马铃薯产量为目标函数建立方程。结果表明:氮、磷、钾需求量,钾肥>氮肥>磷肥,符合马铃薯需肥规律。通过对氮、磷、钾肥与产量的施肥模型进行频次分析得出,黑龙江省哈尔滨地区马铃薯田施肥量:纯N为157.95~162.61 kg/hm2,P2O5为30.59~34.08 kg/hm2,K2O为191.30~204.28 kg/hm2。 相似文献
25.
生姜对氮磷钾吸收分配规律的研究 总被引:12,自引:1,他引:12
生姜对氮、磷、钾的吸收符合Logistic方程之模型,呈“S”型曲线变化,但其吸收比例因不同生育期而异。总的来看,钾的吸收比例最高,氮次之,磷最少,全生育期氮、磷、钾的吸收比例为11.0:1:16.1。生姜各器官氮、磷、钾的含量,除在根内较稳定外,其余均随生长的进行呈下降的趋势。氮、磷、钾向各器官的最终分配量,除钾在地上茎分配略高于根茎外,氮、磷均以地下根茎的分配量最高。 相似文献
26.
Shoot:root (S:R) response in four winter C3-grasses (cereals) viz. wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.) and oats (Avena sativa L.) was investigated under eight different NPK sources (S1 = 20-20-20, S2 = 20-27-5, S3 = 7-22-8, S4 = 10-10-10-20S, S5 = 11-15-11, S6 = 31-11-11, S7 = 24-8-16, and S8 = 19-6-12) in pot experiment at Dryland Agriculture Institute, West Texas A&M University, Canyon, Texas, USA during winter 2009–2010. The experiment was performed in completely randomized design (CRD) with three repeats. The objective of this experiment was to investigate whether the S:R of winter cereals differ or not when applied with different NPK sources. Considerable variations in the shoot: root was noticed in the four grasses at different growth stages, i.e., 30, 60 and 90 days after emergence (DAE) when applied with different NPK fertilizers sources. Wheat had the highest S:R of 3.4 at 30 days after emergence (DAE), barley at 60 DAE (6.5), while oats at 90 DAE (3.9). Among the NPK sources, crops had the highest S:R of 3.6, 6.2 and 3.7 when applied with S3, S2, and S6 at 30, 60 and 90 DAE, respectively. Shoot to root ratio showed positive relationship with increase in shoot weight and negative relationship with increase in root weight. The NPK fertilizer S6 (31: 11: 11), an acid loving fertilizer had negative effects on the shoot and root development of cool season cereals, but among these cereals under study, barley and oats roots were affected more than wheat and rye. It was concluded from this present study, that the four cool season cereals responded differently in terms of shoot: root to different NPK fertilizers at different growth stages. 相似文献
27.
Effect of nutrients and liming on changes in pH,redox potential,and uptake of iron and manganese by wetland rice in iron-toxic soil 总被引:2,自引:0,他引:2
In a greenhouse experiment, the nutrients NPK, NPK + lime, K, and Mn were applied to an iron-toxic soil (Typic Haplastulf). Soil pH and dry matter production were increased and Eh and available Fe in the soil were decreased. Though liming the soil decreased available Fe and Mn and increased pH to the greatest extent, the highest dry matter production was obtained with NPK application. NPK + lime produced a smaller yield than NPK without lime. Though the application of K or Mn alone produced much less dry matter than NPK or NPK + lime, no symptoms of Fe toxicity were observed. We conclude that Fe toxicity can be reduced with a balanced use of fertilizers (NPK or NPK + lime) and its occurrence was mostly due to nutrient stress. 相似文献
28.
M. M. A. Khan Samiullah S. H. Afaq R. M. Afridi 《Journal of Agronomy and Crop Science》1995,174(2):91-98
A pot experiment was conducted on Black nightshade ( Solanum nigrum L.) to study the effect of urea nitrogen and select the optimum dose required for its vegetative and reproductive growth, leaf NPK content, yield of fruit and fruit solasodine. Urea was applied at 0.0, 0.45, 0.90, 1.35, 1.80 and 2.25 g N per pot which contained 3.5 kg soil. Seeds were sown directly in pots and plant samples were drawn at fortnightly intervals for recording growth and yield parameters. In addition, solasodine content in fruit and N, P and K in leaves were also estimated. The results showed that all the parameters were influenced by N. In general, N at 1.80 g per pot was optimal. 相似文献
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Gaurav Sood Rajesh Kaushal Girish Panwar Meenakshi Dhiman 《Communications in Soil Science and Plant Analysis》2019,50(2):141-152
The present study aimed at selection of efficient bacterial isolates with multiple plant growth-promoting (PGP) traits at variable doses of chemical fertilizers for enhanced wheat productivity and sustenance of soil health. Ten bacterial isolates from wheat (rhizosphere soil and root endosphere) were screened for PGP traits (indole acetic acid, phosphate solubilization, siderophore production, and ammonia production). Only three isolates (B2, SIR1, and BIS2) possessed all PGP traits. Net house evaluation of these isolates at graded doses of chemical fertilizers revealed that the potential of B2 isolate is significantly superior for enhancing wheat yield and soil properties. On the basis of 16S rDNA analysis, the potential isolate (B2) was identified as Serratia marcescens. Conjoint use of the B2 isolate at 80% recommended doses of fertilizers (RDF) significantly increased wheat growth and saved 18 kg nitrogen and 10 kg phosphorous on per hectare basis. The developed module not only increases profitability but also protects the environment and sustains soil health. 相似文献