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91.
在高明市采用大田试验方法,研究了蘑菇渣与氮磷钾化肥配合施用对豇豆生长的效应.结果表明:单施蘑菇渣的豇豆产量极低,而蘑菇渣与氮磷钾化肥配合施用的增产效果极显著,一般比单施蘑菇渣可增产362.0%~390.5%;此外,蘑菇渣与氮磷钾化肥配合施用还具有促进豇豆开花结荚、增加豆荚长度、提高豆荚维生素C含量和磷钾含量的效果.从多个指标综合比较,以每667 m2用蘑菇渣500 kg与尿素28.7 kg、过磷酸钙37.9 kg、氯化钾12.7 kg配合施用的效果最佳,可作为当地豇豆高效使用蘑菇渣的推荐施肥措施. 相似文献
92.
Saeed Ahmad Muhammad Mubashar Naeem Muhammad Mosan Malik Muhammad Nafees M. Yaseen 《Journal of plant nutrition》2017,40(6):755-760
This study was carried out to determine the integrated effect of organic matter alone and in combination with chemical fertilizers in order to maintain the nutritional status in Kinnow fruit plants. Lahore Compost was used as a source of organic matter. Treatments were made by using compost alone and in combination with nitrogen, phosphorus, potassium (NPK), and well-rotten farm yard manure (FYM; cow dung). Treatments were applied before flowering and after fruit set. Effect of these treatments on different physicochemical characteristics of Kinnow fruit and nutritional status in tree leaves was determined. Among all treatments, minimum flower drop, maximum yield, and better fruit quality were recorded in plants where 40 kg compost + 1/2 recommended doses of NPK were applied before flowering and after fruit setting, while minimum fruit set was recorded from the plants where 30 kg compost alone was applied before flowering. 相似文献
93.
Fertigation offers vast potential for efficient use of water and nutrients in sustainable orchard management. Beside minimizing losses, their distribution within the rhizosphere is of utmost importance. In present investigations, most of feeder roots were observed within 30 cm soil depth. Under drip fertigation, wetting front extended horizontally up to 45 cm from emitter. However, the maximum moisture content remained confined within 30 cm distance. Vertically, soil moisture also remained higher in the 0–30 cm soil layers. Under surface irrigation, deeper soil layers registered higher moisture content. Available nitrogen (N) and potassium (K) under fertigation closely followed the moisture distribution pattern. Fertigation plus mulch resulted in 20% fertilizer and 15% water savings over fertigation without mulch. Beside 33% higher fruit yield and 25% water savings, and fertigation plus mulch resulted in 20 percent fertilizer and 40% water savings over surface irrigation. 相似文献
94.
95.
The effects of repeated drying-rewetting (DRW) cycles on the microbial biomass and activity in soils taken from long-term field experiment plots with different fertilization (FERT) management practice histories were studied. We investigated the hypothesis that soil response to DRW cycles differs with soil fertility gradient modified by FERT management practices. The soils were incubated for 51 days, after exposure to either nine or three DRW cycles, or remaining at constant moisture content (CMC) at field capacity. We found that both DRW and FERT significantly affected soil properties including NH4-N, NO3-N, dissolved organic C (DOC), microbial biomass C (Cmic), basal soil respiration rate (BSR), urease activity (URE) and dehydrogenase activity (DHD). Except for NH4-N and BSR, variation in the properties was largely explained by FERT, followed by DRW, and then their interaction. Irrespective of the soils' FERT treatment, repeated DRW cycles significantly raised the DOC and Cmic levels compared with CMC, and the DRW cycles also resulted in a significant decline in BSR and URE and increase in DHD, probably because the organisms were better-adapted to the drying and rewetting stresses. The variations in soil biological properties caused by DRW cycles showed a significantly negative relationship with the soil organic C content measured prior to the start of the DRW experiments, suggesting that soils with higher fertility are better able to maintain their original biological functions (i.e., have a higher functional stability) in response to DRW cycles. 相似文献
96.
【目的】探究基于有效积温的不同氮磷钾处理夏玉米株高和叶面积指数(LAI)的生长动态预测模型及其特征参数,以期为利用有效积温定量模拟夏玉米生长发育动态提供理论依据。【方法】在河北廊坊两年大田试验(2019—2020年)基础上,以郑单958为试验材料,分为氮、磷、钾3个单因素肥效试验,每个因素设4个水平,分别为不施肥、低肥、适量肥和高肥处理。采用Logistic模型拟合不同氮磷钾营养水平下夏玉米株高和叶面积指数基于有效积温的动态方程,并利用增长速率曲线及其特征参数定量分析了夏玉米生长发育特征。【结果】(1)在本试验条件下,与其他处理相比,适量施肥处理(N2、P2和K2)夏玉米株高最大值均为最大。过量施用钾肥对夏玉米最大株高有显著的抑制作用。适量施肥处理夏玉米株高进入平台期所需积温为952.43—958.83℃·d。适量施肥能有效增加夏玉米叶面积指数,养分过量或过少均影响叶面积的形成。适量施肥处理夏玉米叶面积指数进入平台期所需积温为849.18—952.43℃·d。(2)各施肥处理条件下以有效积温为自变量建立的夏玉米株高和叶面积指数方程的拟合度R 2分别为0.9949—0.9970和0.98... 相似文献
97.
喷施钙硅对设施春茬番茄根系生长、NPK吸收及产量和水分利用的影响 总被引:1,自引:0,他引:1
以番茄品种鑫语为试验材料,在开花盛果期喷施含Ca(NO_3)_2、Ca(H_2PO_4)_2、KSiO_4、Ca(NO_3)_2+KSiO_4及Ca(H_2PO_4)_2+KSiO_4的悬液,探讨钙硅单一及配合施用对设施春茬番茄根系生长、NPK吸收、产量及水分利用率的影响。结果表明:喷施钙硅悬液显著促进番茄根系生长及发育,显著促进根系和果实磷钾吸收;含钙悬液单独喷施处理的根系和果实氮吸收显著高于硅悬液及钙硅复配悬液;两种含钙悬液Ca(NO_3)_2和Ca(H_2PO_4)_2喷施处理取得最佳调控效果,与对照相比,分别使番茄增产9%和7%,水分利用率提升7、5.5 kg·m~(-3),喷施Ca(NO_3)_2+KSiO_4使番茄增产4.7%,水分利用率提升3.8 kg·m~(-3),喷施Ca(H_2PO_4)_2+KSiO_4和KSiO_4未取得显著的调控效果;含钙悬液单独喷施处理增加番茄产量与其促进根系发育及增加植株N吸收密切相关;两种含钙物质与KSiO_4对番茄产量的影响存在显著的交互效应,对产量的贡献呈:含钙物质含钙物质×KSiO_4KSiO_4。含钙悬液喷施技术简单高效,能实现番茄增产及生物节水能力提升。 相似文献
98.
为明确城镇生活污泥产品的土地利用效果,选取北京地区常用绿化造林树种国槐和银杏新造幼林为研究对象,以城镇生活污泥产品为试验材料,设置15、30、45、60、75 kg/株共5个污泥施用量梯度,以不施污泥为对照,采用随机区组排列方法进行污泥施用效果的对比试验,定期监测林木的生长指标、叶片的叶绿素含量以及叶片的氮(N)、磷(P)、钾(K)含量。结果表明,国槐胸径年增长值、冠幅投影面积年增长值在施入污泥后均有显著提高,当污泥施用量为45 kg/株时达到最大值;国槐叶片叶绿素含量随污泥施用量的增加而增加,在75 kg/株施用量下达到最高水平;施入污泥后国槐叶片的N、K含量变化不显著,高污泥施用量下P含量明显下降。添加不同量污泥后,银杏胸径年增长值、叶绿素含量均高于对照组,单株施用污泥75 kg时取得最大值;不同处理间银杏叶片中的N、P、K含量变化不显著。由此可见,城镇生活污泥产品的合理施用能够促进国槐、银杏的胸径、冠幅的生长以及叶片叶绿素的合成,在一定程度上延长国槐、银杏的绿期,但对两树种叶片中N、P、K元素积累的促进作用不显著。 相似文献
99.
氮磷钾配施对花生产量的影响及效应分析研究 总被引:1,自引:1,他引:1
为探寻大花生新品种‘青花7号’的最佳施肥方案,采用三因素二次回归通用旋转组合设计方法,建立了氮、磷、钾施肥量与产量关系的效应方程。通过对回归方程的检验及效应分析,探讨了氮、磷、钾肥的单因子效应、互作效应和最佳施肥量。结果表明,施氮、磷、钾肥对花生产量具有明显的增产作用,其肥料效应顺序为钾肥>磷肥>氮肥;氮磷互作对花生产量的影响为极显著。对于试验地块种植的花生新品种‘青花7号’获得高产的最佳施肥组合为:氮肥106.08~133.92 kg/hm2,磷肥159.12~200.88 kg/hm2,钾肥为138.28~161.72 kg/hm2。 相似文献
100.
采用氮、磷、钾不同配比施肥,对切花月季卡罗拉的株高、叶片数、最大叶面积、盛花期开花数、最大花冠径、切花枝长度、白粉病发病率、脯氨酸、可溶性糖含量等指标进行测定,结果表明供试的12种氮磷钾配比处理中,处理輥輰訛生长最好,抗白粉病能力最强,N∶P2O5∶K2O的施入量为0.108、0.010、0.057 kg/m2,比例为1∶0.93∶0.53。 相似文献