Effects of urea enhanced with different weathered coal-derived humic acid components on maize yield and fate of fertilizer nitrogen

Humic acid(HA) is a readily available and low-cost material that is used to enhance crop production and reduce nitrogen(N) loss. However, there is little consensus on the efficacy of different HA components. In the current study, a soil column experiment was conducted using the ^(15)N tracer technique in Dezhou City, Shandong Province, China, to compare the effects of urea with and without the addition of weathered coal-derived HA components on maize yield and the fate of fertilizerderived N(fertilizer N). The HA components were incorporated into urea by blending different HA components into molten urea to obtain the three different types of HA-enhanced urea(HAU). At harvest, the aboveground dry biomass of plants grown with HAU was enhanced by 11.50–21.33% when compared to that of plants grown with U. More significantly, the grain yields under the HAU treatments were 5.58–18.67% higher than the yield under the urea treatment. These higher yields were due to an increase in the number of kernels per plant rather than the weight of individual kernels. The uptake of fertilizer N under the HAU treatments was also higher than that under the urea treatment by 11.49–29.46%, while the unaccounted N loss decreased by 12.37–30.05%. More fertilizer-derived N was retained in the 0–30 cm soil layer under the HAU treatments than that under the urea treatment, while less N was retained in the 30–90 cm soil layer. The total residual amount of fertilizer N in the soil column, however, did not differ significantly between the treatments. Of the three HAU treatments investigated, the one with an HA fraction derived from extraction with pH values ranging from 6 to 7, resulted in the best improvement in all assessment targets. This is likely due to the abundance of the COO/C–N=O group in this HA component.

Effects of Plant-derived Humic Acid Organic Fertilizer on Selenium Content of Rice in Northern Guangxi

This study was to find out the suitable application amount of plant-derived humic acid organic fertilizer for selenium-rich rice production in northern Guilin area by applying the fertilizer at different amounts.The results showed that plant-derived humic acid organic fertilizer could effectively activate selenium in selenium-rich soil,and then promote the uptake of selenium by rice.With costs,selenium enrichment and rice yield as the main evaluation indicators,A4 was chosen as the best treatment,that is,the application of 4 500 kg/hm^2 of plant-derived humic acid organic fertilizer as base fertilizer could achieve the best benefit.

Effects of Nano-carbon Humic Acid Water-retaining Fertilizer on Citrus Growth and the Soil Bacterial Community in Citrus Field

[Objective] In order to reveal the effects of reducing the amount of novel nano-carbon humic acid water-retaining fertilizer(CSF) on soil microbial community structure and citrus growth. [Method]In this study,conventional fertilization was as the control(KC1) in Wanzhou citrus orchard of Three Gorges Reservoir area. CSF reductions by 0%(KC2),10%(KC3),20%(KC4),30%(KC5) and 40%(KC6) were used to analyze the changes of soil bacterial community structure,citrus yield and quality. [Result]The results showed that the observed species,Shannon index,Chao1 index and PDwholetree of KC6 were higher than those of KC1,and were the same as KC2. The abundance of Xanthomonadaceae was the highest in KC5. Compared with KC1,the Xanthomonadaceae in KC3,KC4 and KC6 was significantly decreased,and the levels of Nitrosomonadaceae and Pseudomonasaceae were higher than that of KC1 after the treatment of KC6. Sphingomonas in different reduction treatments was lower than that of KC1,but Burkholderia and Pseudomonas were significantly higher than those of KC1. It was found that the similarity among treatments was small after bacterial community similarity clustering analysis,and citrus yield increased somewhat after CSF fertilization reduction.When CSF fertilization reduced by 30%,citrus yield increased by 4. 50%. When CSF fertilization reduced by 40%,citrus yield decreased by4. 14%. After CSF fertilization,citrus quality did not change significantly in CSF conventional fertilization and reduction of 10% and 40%,while significantly decreased in 20% and 30% of fertilization reduction. [Conclusion] CSF fertilization reduction changed the diversity of soil bacterial community structure and the yield and quality of citrus.

Experiment of Water Soluble Fertilizers Containing Humic Acid in Tomato Planting

As a natural macromolecular organic compound,humic acid can promote plant growth.Water soluble humic acid fertilizers refer to liquid or solid water soluble fertilizers made by adding appropriate amounts of nitrogen,phosphorus,potassium macroelements or zinc,boron,iron,molybdenum,manganese,copper and other trace elements or organic matter,based on humic acid in the required proportions for plant growth.In order to verify the application effect of humic acid containing water soluble fertilizer produced by Tai’an Gold Land Chemical Co.,Ltd.,in tomato production in Daiyue District,Tai’an City,a fertilizer effect application experiment of humic acid containing water soluble fertilizer on tomato planting was specially carried out.The results showed that the water soluble fertilizer containing humic acid could obviously improve the agronomic characters of tomato;the yield was significantly increased;the effect of increasing the income of tomato growers was obvious.

Carbon Sequestration in Soil Humic Substances Under Long-Term Fertilization in a Wheat-Maize System from North China

The changes in humic substances （HS） is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances （WSS）, humic acid （HA）, fulvic acid （FA） and humin （HU） were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were significant different among the treatments with manure. A significant correlation was found between the increased soil organic carbon （SOC） and HS （R^2=0.98, P〈0.01）. The change in the E4/E6 ratio was significantly correlated with the increased SOC （R2=0.88, P〈0.01）, HA （R^2=0.91, P〈0.01）, FA （R^2=0.91, P〈0.01） and HU （R^2=0.88, P〈0.01）. The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization.

微咸水-腐植酸肥耦合滴灌条件下钙镁离子质量浓度对灌水器堵塞的影响

【目的】探明腐植酸肥施用条件下不同钙镁离子质量浓度对灌水器堵塞物质形成的影响效应与作用机制。【方法】以微咸水中钙镁离子耦合腐植酸肥滴灌为研究对象,选取4种不同额定流量(1.6、1.1、1.4、1.75 L/h)的非压力补偿内镶贴片式灌水器(FE1—FE4),其中设置3组钙离子质量浓度微咸水处理,离子质量浓度分别为100、150、200 mg/L(G1、G2、G3),3组镁离子质量浓度微咸水处理,离子质量浓度分别为100、150、200 mg/L(M1、M2、M3),以地下微咸水灌溉为对照(CK),研究不同离子质量浓度的灌水器平均流量(Dra)、滴灌系统灌水器的堵塞率分布、灌水器堵塞物质干质量(DW)动态变化规律,并分析了灌水器内部堵塞物质矿物组分。【结果】与CK相比,G1、G2、G3、M1、M2、M3处理的Dra分别降低了21.58%~29.68%、35.02%~39.71%、45.62%~55.68%、14.25%~20.41%、24.89%~45.69%、35.22%~56.75%,堵塞物质干质量分别增加了124.62%~178.49%、174.23%~230.33%、235.59%~270.09%、67.14%~120.28%、136.96%~191.18%、203.54%~213.35%。与G1、G2、G3处理相比,质量浓度相同镁离子处理M1、M2、M3处理的堵塞物质干质量分别降低了16.41%~27.26%、4.77%~13.60%、6.82%~15.34%。【结论】钙镁离子质量浓度的增加均显著加剧了灌水器的堵塞;在相同离子质量浓度条件下,镁离子处理显著减少了灌水器内堵塞物质的总量,因此镁离子在一定程度上能够降低灌水器堵塞风险。

腐殖酸水溶肥料对毛豆生长的影响

毛豆,又称菜用大豆(Glycine max L.),其味道鲜香营养价值高,是一种重要的豆科蔬菜。在减施化肥条件下,腐殖酸作为替代化肥的有机肥料的最佳选择之一。本试验探讨腐殖酸水溶肥对毛豆生长的影响,用早熟毛豆品种沪宁95-1毛豆作为试验材料,设置3次重复,分析0 g/L(T0),1 g/L(T1),2 g/L(T2)腐殖酸水溶肥浓度下对毛豆的发芽率、株高、叶绿素等含量的影响。结果表明,T1处理的发芽率比对照增加了15.0%,T1和T2处理的株高分别比对照增加了12.8%和6.8%,其中,T1处理有显著性促进效果;T1处理单株荚数、单株荚重和百粒重均显著高于对照,分别比对照增加42.3%、48.6%和20.7%。叶绿素含量和对照相比分别增加了12.7%和6.7%;T1和T2处理均显著性地促进了可溶性糖含量,分别增加了35.3%和63.5%。结果显示,施加1 g/L浓度的腐殖酸水溶肥可以提高毛豆的发芽率、株高、叶绿素含量和可溶性糖含量。

水解-氧化法制备甘蔗叶生物质腐植酸

本研究以甘蔗叶为原料,通过设计模拟矿源腐植酸形成过程中的化学反应,研究将甘蔗叶转化为腐植酸的技术,并将实验室制得的腐植酸与矿源腐植酸和木质素进行比较研究。制备过程:首先进行酸水解反应,将其中的纤维素和半纤维素水解为可溶解的水解糖,将木质素转化为不溶的腐植酸前体,固液分离;然后用氧化剂对腐植酸前体进行氧化反应,重新生成亲水性的羧基基团,完成腐植酸的制备。实验结果表明,水解反应步骤时,在固定20∶50(g∶mL)固液比的条件下,最佳的反应条件为:10%的硫酸和1%的硝酸组成的水解液,在150℃的温度下,水解3 h;氧化步骤中,腐植酸前体以1∶13(g∶mL)的固液比与3.5%的硝酸在80℃的温度下反应2 h。经元素分析、酸性基团分析、紫外和红外光谱以及核磁共振波谱等一系列分析手段,证实制备的蔗叶生物质腐植酸有较高的腐殖化和芳香化程度,其各项指标均接近于矿源腐植酸。该方法能成功制备腐植酸,同时利用产生的水解糖还具备与多种现有生物质产业相结合的潜在可能,以解决其水解残渣的问题。

施用不同品种氮肥对麦套花生生长和产量的影响

为研究砂质土壤上追施不同类型氮肥对麦套花生生长发育和产量的影响,在河南新乡市开展田间试验,分别设置不施肥(对照)、施用氯化铵、硫酸铵、硝酸铵钙、普通尿素、腐植酸尿素、控释尿素共7个处理,分析不同处理对花生株高、分枝数、复叶数、干物质和产量的影响。结果表明,与对照相比,施用不同类型氮肥均提高了花生的株高,其中尿素处理的株高在各个时期均较高;腐植酸尿素和控释尿素处理的株高在生育后期较高。施用氮肥能促进花生分枝,下针期以前以氯化铵、尿素和控释尿素处理的增幅较大。氮肥类型显著影响花生复叶数,其中硫酸铵和硝酸铵钙处理花生的复叶数在生育前期较少而后期较多;腐植酸尿素和控释尿素处理在前期较多但成熟期较少;氯化铵和尿素处理在整个生育期则较为平稳。施用各类型氮肥均显著提高了花生膨果期和成熟期的干物质量。与对照相比,追施不同类型氮肥可增产25.0%~61.0%,其中硝酸铵钙和腐植酸尿素增产幅度最大;尿素和控释尿素的增产效果高于硫酸铵和氯化铵;且施用硝酸铵钙、尿素和控释尿素处理花生的坏果率低于其他处理。综上所述,本研究条件下,麦套花生追施氮肥可促进花生生长并提高产量,其中硝酸铵钙的增产效果最佳;腐植酸尿素和控释尿素也具有较好效果。

含腐植酸水溶肥对空心菜生长及土壤养分性状的影响

为研究不同含腐植酸水溶肥施用量及施肥方式对空心菜品质、土壤含碳量、养分含量、土壤酶活性的影响,设置8个处理,分别为空白(CK)、常规化肥(CF)、根施腐植酸水溶肥全量替代(RT_(1))、根施腐植酸水溶肥50%替代(RT_(0.5))、根施腐植酸水溶肥25%替代(RT_(0.25))、叶施腐植酸水溶肥全量替代(LT_(1))、叶施腐植酸水溶肥50%替代(LT_(0.5))、叶施腐植酸水溶肥25%替代(LT_(0.25)),测定收获后土壤理化性质以及空心菜产量品质指标,采用主成分分析法对施肥效果进行综合评价。结果表明,RT_(1)较CF产量、土壤有机碳(SOC)含量和可溶性固形物含量分别提升了11.5%、8.7%和8.8%;LT_(1)较CF可溶性固形物、粗蛋白和维生素C含量分别提升了17.6%、15.5%和11.0%,但产量和土壤SOC含量分别下降了2.9%和11.3%。空心菜产量与土壤速效氮和SOC含量呈显著正相关(P<0.05),与pH和速效钾、速效磷含量呈显著负相关(P<0.05),表明速效氮养分和有机质的添加对于促进空心菜的生长和增加产量起重要作用。根据主成分分析结果,施加含腐植酸水溶肥有利于高品质蔬菜生产及提高土壤质量,根部施用全量含腐植酸水溶肥替代化肥(RT_(1))效果最佳。研究结果可为提高作物产量品质和土壤质量,实现化肥减施并增加土壤固碳能力提供参考。

不同比例有机肥替代化肥对甜菜植株养分及产量的影响

【目的】研究不同比例有机肥替代化肥对土壤养分含量、植株养分吸收量、肥料利用率以及甜菜产量和质量的影响,为甜菜高产稳产、土壤培肥提供科学施肥依据。【方法】试验共设置7个处理:不施肥对照(CK),常规施肥(CF),腐殖酸有机肥替代10%化肥(10%HF),腐殖酸有机肥替代20%化肥(20%HF),腐殖酸有机肥替代30%化肥(30%HF),腐殖酸有机肥替代40%化肥(40%HF),腐殖酸有机肥替代50%化肥(50%HF)。测定土壤养分、甜菜植株养分吸收量以及甜菜干物质积累量、产量和品质。【结果】腐殖酸有机肥替代部分化肥处理较常规施肥处理增加土壤有机肥含量2.37%~7.38%;碱解氮、速效磷、速效钾分别增加1.07%~11.39%、10.65%~37.83%、6.04%~14.68%,30%HF与处理40%HF分别较CF处理显著增产16.91%与17.65%。【结论】腐殖酸有机肥替代不同比例化肥较常规施用化肥可以显著提升土壤养分含量,提高甜菜植株养分吸收量,增加甜菜干物质积累量、减施化肥、培肥土壤、增加产量,其中有机肥替代30%化肥处理增产与培肥地力的效果较优。

烤烟苗期施用腐殖酸肥对低温胁迫的响应

【目的】为应对湘南稻作烟区烤烟移栽期低温阴雨天气,促进烤烟早生快发。【方法】采用盆栽试验,研究腐殖酸肥(全能有机碳肥)在低温胁迫下对烟苗地上部分生长、根系生长、干物质积累与分配、叶片SPAD值、硝酸还原酶(NR)活性、丙二醛含量和抗氧化酶活性的影响。【结果】腐殖酸肥质量浓度对低温胁迫下烤烟生长发育具有双重效果,表现为低质量浓度促进、高质量浓度抑制。适量施用腐殖酸肥(单株417~833 mg)可减缓低温胁迫对烟苗的损伤,促进其根系和地上部生长、干物质积累以及烟苗根系活力,叶片SPAD值提高4.64%~5.80%,超氧化物歧化酶(SOD)活性提升23.20%~50.26%,过氧化氢酶(CAT)活性提升5.39%~9.54%,过氧化物酶(POD)活性提升137.29%~151.43%;还可提高低温胁迫后烟苗的恢复生长能力,叶片SPAD值提高7.87%~10.64%,NR活性提升30.30%~42.42%,CAT活性提升0.89%~26.72%,POD活性提升90.91%~145.45%。【结论】施用腐殖酸肥可提高烟苗抗寒能力和恢复生长能力,有利于南方稻茬烟区烟苗早生快发。

不同施肥组合对科尔沁沙地南缘沙地土壤健康指标的影响

为研究不同施肥组合对沙地土壤改良的效果,以辽宁省阜新市彰武县的沙地土壤为考察对象,开展了试验研究。试验以不施肥为对照(CK)处理,设置生物有机肥分别与含腐殖酸肥料(OH)、含聚谷氨酸肥料(OP)和中微量元素肥(OM)混施3个施肥处理,测定施肥后6、12、18个月的土壤中微生物数量和土壤理化性状的变化。结果表明:不同施肥处理的土壤中微生物数量均呈现细菌>放线菌>真菌的变化趋势,其中OH处理的细菌数量最多,3个取样时间的细菌数量平均值为1.510×10^(7)cfu/g,是CK处理的5.2倍;施肥处理的土壤中全磷、全钾和有机质含量均得到提高,OP处理的全钾含量平均值最高,质量分数为5.96 g/kg;施肥处理的土壤pH均呈下降趋势;施肥处理的地上部植物生物量提高。施用不同组合的肥料可以有效提高土壤微生物的数量,改善土壤理化性状,提高地上部植物生物量,是一种合理的沙地改良措施。

噻苯隆作用下叶面肥养分组成变化对小麦生理代谢和产品要素的影响

为探究噻苯隆作用下叶面肥养分组成变化孕穗期喷施对小麦生理代谢、氮素吸收利用以及籽粒产量和品质的影响,以小麦“烟农19号”为试验材料,设置8个盆栽试验处理:A0(3.3mg·L^(-1)噻苯隆)、A1(3.3mg·L^(-1)噻苯隆+腐殖酸叶面肥)、A2(3.3 mg·L^(-1)噻苯隆+缺氮腐殖酸叶面肥)、A3(3.3 mg·L^(-1)噻苯隆+缺磷腐殖酸叶面肥)、A4(3.3 mg·L^(-1)噻苯隆+缺钾腐殖酸叶面肥)、A5(3.3 mg·L^(-1)噻苯隆+缺氨基酸腐殖酸叶面肥)、A6(3.3 mg·L^(-1)噻苯隆+缺硼腐殖酸叶面肥)和A7(3.3 mg·L^(-1)噻苯隆+缺腐殖酸叶面肥),每个处理重复3次。于2022年4月在小麦孕穗期后的1 d、5 d和9 d开始喷施,每次喷施量为150 mL。结果表明:叶面施肥能够提高叶片中叶绿素含量,但对类胡萝卜素含量影响不显著,同时促进可溶性糖的合成和抗氧化酶活性提高,其中氮、磷养分缺失会抑制过氧化氢酶活性,较A1处理降低了26.40%~31.12%;对于氮代谢,叶面施肥能够促进小麦对氮素的吸收和转化,其中氮、磷和硼缺失会降低叶片可溶性蛋白含量,抑制谷氨酸合成酶的活性,缺钾则会抑制叶片谷氨酰胺合成酶活性,相比于A1处理活性降低了20.38%。叶面施肥能够不同程度地提高小麦籽粒产量,增加穗粒数和千粒重,但对总穗数影响不显著,而钾和氨基酸缺失则会降低小麦穗粒数;同时能够改善籽粒品质,增加籽粒中粗蛋白及蛋白组分含量,但影响不显著,而钾、氨基酸和硼缺失影响籽粒中清蛋白和球蛋白的合成。在噻苯隆的作用下,叶面肥中氮、磷、钾元素组成对小麦生理效应影响显著。研究结果为叶面肥养分配比的选择提供基础理论支持。

喷施腐殖酸肥对万寿菊现蕾期农艺性状与生理指标的影响

以万寿菊为试材,采用温室栽培方法,研究了万寿菊现蕾期叶面喷施腐殖酸类肥料对其农艺性状和生理指标的影响,以期为腐殖酸类肥料应用于万寿菊大田生产中的施用提供参考依据。结果表明:与对照相比,喷施腐殖酸水溶肥HA后万寿菊的二级分枝数与花朵数显著提高,且单株总产量提高了16.02%(P<0.05)。万寿菊叶片的可溶性糖、可溶性蛋白质和叶绿素含量分别增加10.70%、7.02%和7.41%。此外万寿菊叶片中的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性显著提升,而过氧化氢(H_(2)O_(2))和丙二醛(MDA)含量分别减少10.66%、12.26%。喷施黄腐酸水溶肥FA后过氧化物酶(POD)活性显著提升。综上,在现蕾期叶面喷施HA可显著促进万寿菊的生长,可为提高大田产量提供实际指导依据。

“科庆”牌腐植酸液体肥料在冬小麦上的应用

根据产业项目发展要求,以“科庆”牌腐植酸液体肥料为基础,在宿豫区曹集乡快乐居沈庄组进行冬小麦应用效果研究。结果表明,喷施腐植酸液体肥料后,小麦出叶速度快,植株鲜重和干重均增加,分蘖增多;每亩穗数增加,单穗重增加,千粒重提高,亩产量增长迅速,每亩产量平均增长35.2 kg,增产幅度达到7.9%。试验结果表明,“科庆”牌腐植酸液体肥料对小麦有促进生长发育、增产的作用,在小麦的生产应用上具有较好的应用前景。

腐植酸复合肥对玉米生长及养分吸收的影响

为了解不含腐植酸尿素和添加了不同剂量腐植酸的复合肥对玉米生长及养分吸收的影响,研究设定不同的肥料梯度和肥料配比,以探明腐植酸肥料的增产效果和养分利用率.以玉米为试验材料,设无氮处理、复合肥处理、1‰腐植酸+复合肥处理、2‰腐植酸+复合肥处理、3‰腐植酸+复合肥处理、4‰腐植酸+复合肥处理、5‰腐植酸+复合肥处理、6‰腐植酸+复合肥处理共8个施肥处理.试验结果表明,4‰腐植酸复合肥较无氮处理增产率达90%,百粒质量最高,含淀粉量达59.30%,在处理中最具有优势.从综合情况来看,在夏玉米栽培中,加入4‰腐植酸复合肥更有利于玉米增产增效以及贮藏,能获得更大的生物产量和经济效益.

氨基酸肥和腐植酸肥配施尿素对土壤有效氮及辣椒产量的影响

以“美国红”辣椒为试材,采用大田试验方法,在相同供氮水平下,共设置不施肥(CK)、常规施肥(F)、40%氨基酸肥N+60%尿素N(FA)、40%腐植酸肥N+60%尿素N(FH)、20%氨基酸肥N+20%腐植酸肥N+60%尿素N(FAH)5个处理,研究了氨基酸肥和腐植酸肥配施尿素对辣椒土壤有效氮、微生物量氮含量、相关酶活性及辣椒产量的影响,以期为河西灌区辣椒土壤的培肥模式提供参考依据。结果表明:各处理根际土壤氮供应指标、生物学特性指标含量均为各土层中最高,氨基酸肥、腐植酸肥配施尿素对比单施尿素对土壤全氮提升效果并不明显,但对土壤有效氮、土壤微生物量氮、土壤脲酶活性提升效果显著,氨基酸肥、腐植酸肥配施尿素能够有效提高辣椒产量,改善辣椒干物质分配比例。各处理以FA处理提升效果最为明显。根际土中,对比单施尿素土壤铵态氮、硝态氮含量分别提升了12.69%、27.58%;0~20 cm土层中,对比单施尿素土壤铵态氮、硝态氮含量分别提升了14.24%、41.75%;20~40 cm土层中,对比单施尿素土壤铵态氮、硝态氮含量分别提升了21.47%、58.85%。F、FA、FH、FAH处理每667 m^(2)产量对比CK增产率分别为10.72%、15.19%、14.64%、12.92%。相关性分析表明各指标间呈极显著正相关。由此可见,氨基酸、腐植酸肥配施尿素能够有效提高土壤有效氮含量及辣椒产量,且各处理以40%氨基酸肥+60%尿素提升潜力最大。

腐植酸水溶肥在小麦田上的应用效果研究

[目的]通过田间小区试验,研究叶面喷施腐植酸水溶肥对冬小麦生长、产量构成因素及经济效益的影响。[方法]以徐麦35为材料,采用叶面喷施水溶肥的方式,在小麦返青期、拔节期和孕穗期各喷施1次腐植酸类叶面肥,得出施用效果。[结果]腐植酸水溶肥能增加小麦的穗数、穗粒数和千粒重,增产率达10.58%,增产效果显著,产投比为5.76∶1,经济效益明显。[结论]安徽华润公司生产的含腐植酸叶面肥可以在凤阳县大面积推广应用。

腐植酸水溶肥对枇杷幼苗生长的影响

为研究叶面喷施腐植酸水溶肥对枇杷[Eriobotrya japonica(Thunb.)Lindl.]幼苗生长的影响,以大五星枇杷幼苗为材料,叶面喷施不同稀释浓度(700、1 000、1 300、1 600倍)的腐植酸水溶肥,以喷施等量清水为对照(CK),测定腐植酸水溶肥对枇杷幼苗生物量、光合色素含量和抗氧化酶活性的影响。结果表明,叶面喷施不同浓度的腐植酸水溶肥提高了枇杷幼苗茎杆和叶片生物量、光合色素含量,且均以稀释1 000倍效果最好。稀释1 000、1 300倍腐植酸水溶肥处理提高了枇杷幼苗过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性。枇杷幼苗茎杆、叶片生物量与叶绿素a、叶绿素b、类胡萝卜素含量、CAT活性、POD活性和SOD活性呈正相关。因此,叶面喷施腐植酸水溶肥能够促进枇杷幼苗生长,且以稀释1 000倍最佳。