Study on the Changes of Physiological Indexes of Water Spinach in Eutrophication Water

[Objective] Effect of hypoxic water culture on physiological characteristic of water spinach and its hypoxia tolerance were studied.[Method] Water spinach was planted in soil and eutrophication water by means of floating bed,respectively,and the change of physiological indexes including chlorophyll,proline（Pro）,malondialdehyde（MDA）,soluble sugar and soluble protein in water spinach leaves at mature stage was researched,while the hypoxia tolerance of water spinach and the effect of plant density on water spinach growth were discussed in our paper.[Result] In the hypoxic eutrophication water,the content of total chlorophyll,malondialdehyde,soluble sugar and soluble protein in water spinach leaves was lower than that of soil culture,with higher proline content,which showed that water spinach had better tolerance to hypoxic eutrophication water;the higher the plant density,the lower the chlorophyll content in water spinach leaves,and there was no significant effect of plant density on proline and malondialdehyde content,while soluble protein content was higher under high plant density.[Conclusion] The best plant density of water spinach was 66 plants per floating bed with the area of 2 m2,which could provide theoretical basis for the application of water spinach in floating bed.

Chromium Biosorption by Dried Biomass of Water Spinach （Ipomoea Aquatica）

Chromium is a toxic heavy metal that is widely used in industries such as metallurgical industries, and tannery industries. This study investigates the use of an alternative adsorption technology, biosorption, using dried biomass of water spinach （Ipomoea aquatica） in removing chromium from aqueous solutions. Dried biomass was prepared through washing, drying, cutting and alkali treatment. K,Cr207 solutions at an initial concentration of 200~ 14.72 mg/L were added to biomass weight of 200.0~ 1.1 mg at varying pH values of 1.00, 2.00, 3.00~0.02, 4.00~0.58 and 5.00~0.44. The maximum total chromium ion uptake was at pH=2, wherein the biomass adsorbed was 9.56~0.64 ppm Cr/mg biomass. K2Cr207 solutions at concentrations of 10.00~0.32, 50.00~0.95, 100.00~0.76, 200.00~4.82 and 300.00~4.69 mg/L were added to flasks with a biomass weight of 200.00~0.75 mg and pH of 2.00~0.25. The behavior of chromium ion biosorption unto the dried water spinach best fits the Langmuir isotherm with a coefficient of determination （R2） value of 0.9993. The calculated maximum adsorption （%） is 0.13889 kg/kg. The adsorption equilibrium constant （K） is 1705.83 mg/L. The continuous experiment showed that the kinetic behavior of the biomass in a packed bed column followed the following equation with a coefficient of determination （R2） value of 0.7039： C/C0=0.266e^-0.004t

Biomass Accumulation and Water Purification of Water Spinach Planted on Water Surface by Floating Beds for Treating Biogas Slurry

To find a new way treating the wastewater from biogas reactors in a pig farm, vegetated floating bed was built for observing the water-purifying capability of water spinach (Ipomoea aquatic) planted on the water surface. Experiments were carried out to record the growth and biomass accumulation of water spinach and its effect on purification of biogas wastewater. The results show that the water which mixed with biogas wastewater has been purified significantly by water spinach on the floating bed. During its growth season within four months, the overall length of water spinach reached 199 ± 35 cm, while its root length reached 63 ± 28.6 cm. The average weight of individual fresh plant is of 1285 ± 619.7 g. Meanwhile, the concentration of total nitrogen (TN) in water under the floating bed decreased from 8.9 ± 0.062 mg·L-1 to 0.5 ± 0.011 mg·L-1;the concentration of total phosphorus (TP) decreased from 4.4 ± 0.236 mg·L-1 to 0.92 ± 0.024 mg·L-1;the concentration of chemical oxygen demand (COD) decreased from 87.3 ± 6.68 mg·L-1 to 0.74 ± 0.46 mg·L-1. It suggests that the water spinach removed more than 90% of pollutants in terms of TN, TP, and COD from the water. Results show that the vegetated floating bed technique is a feasible way to dispose the biogas slurry.

Effects of Biochar and Super Absorbent Polymer on Substrate Properties and Water Spinach Growth

Most previous researches have focused on biochar application in agricultural soils; however, limited information is available concerning the effects of biochar amendment on greenhouse substrate properties. A greenhouse experiment was conducted to investigate effects of wheat straw biochar （0-160 mL L-1） and super absorbent polymer （SAP, 0.8 g L-1） on physical and chemical properties of a substrate based on spent pig litter compost and the growth of water spinach （Ipomoea aquatica Forsk）. Total porosity, water-holding capacity~ pH and electrical conductivity （EC） of the substrate significantly increased with increasing biochar rates, especially in the substrate without SAP. The values of pH and EC were significantly lower in the substrate with SAP than those without SAP at the high biochar application rates （100-160 mL L-l）. The germination rates of water spinach decreased with increasing biochar rates when biochar was added alone （76.9%-83.7%）, whereas the rates increased to 83.6%-85.8% when biochar was added in combination with SAP. Growth parameters of water spinach and nutrient uptake by shoots and roots increased with increasing biochar rates and reached the maximum values at the biochar rate of 100 mL L-1. There were significant cubic relationships between the uptake of nutrients （N, P, and K） and biochar rates, both with and without SAP addition. In order to avoid negative effects on plant growth, the biochar application rate should be controlled at an optimal level （100 mL L-1 ）. The SAP addition not only enhanced the positive effects of biochar application on the properties of the substrate, but also inhibited the excessive rise of pH and EC following biochar additions, which led to better plant growth and enhanced nutrient uptakes by water spinach.

Variations in cadmium and nitrate co-accumulation among water spinach genotypes and implications for screening safe genotypes for human consumptionVariations in cadmium and nitrate co-accumulation among water spinach genotypes and implications for screenin

Vegetables are important constituents of the human diet. Heavy metals and nitrate are among the major contaminants of vegetables. Consumption of vegetables and fruits with accumulated heavy metals and nitrate has the potential to damage different body organs leading to unwanted effects. Breeding vegetables with low heavy metal and nitrate contaminants is a cost-effective approach. We investigated 38 water spinach genotypes for low Cd and nitrate co-accumulation. Four genotypes, i.e. JXDY, GZQL, XGDB, and B888, were found to have low co-accumulation of Cd （〈0.71 mg/kg dry weight） and nitrate （〈3100 mg/kg fresh weight） in the edible parts when grown in soils with moderate contamination of both Cd （1.10 mg/kg） and nitrate （235.2 mg/kg）. These genotypes should be appropriate with mini- mized risk to humans who consume them. The Cd levels in the edible parts of water spinach were positively correlated with the concentration of Pb or Zn, but Cd, Pb, or Zn was negatively correlated with P concentration. These results indicate that these three heavy metals may be absorbed into the plant in similar proportions or in combination, mini- mizing the influx to aerial parts. Increasing P fertilizer application rates appears to prevent heavy metal and nitrate translocation to shoot tissues and the edible parts of water spinach on co-contaminated soils.

Lead Remediation of Contaminated Water by Charcoal, LA Red Clay, Spinach, and Mustard Green

Lead is a toxic and naturally occurring substance with documented neurotoxin, toxic, and long-lasting adverse health effects globally. Lead exposure can cause impaired physical and mental development in children. Exposure to high lead levels affects the intestinal tract, kidneys, joints and reproductive system in adults. This study evaluates the removal of 1500 PPM of lead from contaminated aqueous solution using Celite, Louisiana Red Clay, Charcoal, and supernatants from aqueous extracts of Mustard Green (Brassica juncea), and Spinach (Spinacea oleracea). After shaking triplicate reaction mixtures for each substrate for 22 hours at room temperature, lead removal by the five substrates were analyzed by EPA Method 6010, using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). Results suggest that the order of lead removal is Spinach (98%) > Charcoal (96%) > LA Red Clay (88%) > Mustard Green (87%) > Celite (4%). The study concludes that liquid substrates such as the supernatants from pureed spinach and mustard green can effectively remove lead from contaminated water.

芽孢杆菌及其胞外多糖对空心菜和茼蒿Cd吸收及土壤团聚体的影响

本研究旨在探究产胞外多糖芽孢杆菌对蔬菜镉(Cd)积累及土壤结构的影响。采用以空心菜和茼蒿为供试材料的盆栽试验,研究了功能菌株Priestia megaterium YG35和Bacillus halodurans G20降低蔬菜吸收Cd的效果和可能作用机制。结果表明,与CK相比,菌株YG35、菌株G20及其胞外多糖处理显著增加空心菜和茼蒿可食用组织干质量(37.8%~115.1%),显著降低可食用组织Cd含量(21.9%~44.2%),并使茼蒿Cd含量(0.057~0.061 mg·kg-1)达到安全可食用标准,显著降低根际土壤有效态Cd含量(3.7%~11.7%),显著(P<0.05)增加根际土壤多糖含量(35.9%~49.5%)和蔗糖酶活性(15.3%~28.4%),促进根际土壤团聚体向大粒径转化。研究表明,YG35和G20及其胞外多糖能降低蔬菜对Cd的吸收,促进蔬菜生长,改善土壤结构,具有在Cd污染土壤上实现蔬菜安全生产的应用潜力。

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。

蔬菜型人工湿地资源化处理农村分散生活污水

为对农村分散生活污水进行资源化处理,以空心菜为湿地植物,在温度(32±2)℃、水力负荷2.40 m^(3)/(m^(2)·d)条件下进行湿地污水处理实验,评价了蔬菜型人工湿地对污水的处理性能及其资源化回收潜能。结果表明,当COD、TP、NH_(4)^(+)-N平均进水浓度分别为198.52、2.92、20.69 mg/L时,平均去除率分别为63.8%、64.0%、27.6%,将COD、TP、NH_(4)^(+)-N平均进水浓度降低为148.12、1.81、15.14 mg/L时,湿地去除效果明显提升,平均去除率分别为76.5%、73.0%、41.3%,平均出水浓度分别为34.83、0.49、8.89 mg/L,出水COD、TP、TN达到《城镇污水处理厂污染物排放标准》(GB 8918-2002)一级A标准,NH_(4)^(+)-N达到二级标准,实验期间空心菜生长状态良好,每株平均增重45.88 g,增长47 cm,具有较大的资源回收潜力。

蕹菜开花特性和繁育系统初探

为解决蕹菜品种间花期不遇、有性杂交困难的问题,通过对渔场蕹菜、泰国大叶蕹菜、汝城蕹菜和长沙藤蕹4个蕹菜亲本的开花特性和繁育系统观测和11 h·d^(-1)短日照调控蕹菜品种的花期,并开展了蕹菜品种间有性杂交。结果表明,蕹菜自然光周期条件下现蕾期为8—11月份,刈割发芽后短日照诱导11~13 d现蕾,现蕾至开花11 d左右,单花开放时间约12 h;开花当天09:00—13:00花粉活力最高,11:00—13:00柱头可授性最强;渔场蕹菜和长沙藤蕹花粉/胚珠比(P/O值)、杂交指数(OCI值)基本一致,但长沙藤蕹在控制授粉试验中表现为自交不结实;花粉粒为球状或帽状,表面布满尖刺;以籽蕹品种为母本的杂交结实率最高可达75.00%,结籽率高;长沙藤蕹为母本的杂交结实率最高可达6.00%,结籽率为0。综合分析表明,蕹菜繁育系统倾向于异交混合交配型,11 h·d^(-1)短日照处理可以实现蕹菜品种间花期相遇,蕹菜品种间杂交亲和,但长沙藤蕹有可能丧失了结籽能力。

蕹菜盲样中多种农药残留的测定能力验证结果与分析

通过参加湖南省农业农村厅组织的2023年农产品质量安全检测能力验证工作,评价永州市食品质量安全监督检测检验中心农药残留检测能力水平。本次考核依据作业指导书,参考NY/T 761-2008中农药残留检测的基本操作,采用气相色谱法对收到的蕹菜盲样进行检测,采用外标法定量。本次考核样品SY23100检出乙酰甲胺磷的含量为0.131 mg·kg^(-1),倍硫磷的含量为0.076 mg·kg^(-1),对硫磷的含量为0.050 mg·kg^(-1),腐霉利的含量为0.073 mg·kg^(-1),溴氰菊酯的含量为0.129 mg·kg^(-1),氟氯氰菊酯的含量为0.081 mg·kg^(-1)。结果上报一个月后收到反馈结果为合格,通过此次能力验证。

海南市售蕹菜重金属含量分析

采用内梅罗综合和单因子污染指数法,以海南省18个市县连续采集的108份市售蕹菜试样材料作为研究对象。电感耦合等离子体质谱技术同时测定蕹菜中As、Cd、Hg、Pb、Cr、Ni、Zn和Cu这8种元素的含量。结果表明,该方法回收率为90.8%~106.0%,相对标准偏差为0.41%~1.14%;在0~100μg·L^(-1)浓度范围内,线性良好,方法简单便捷可行;蕹菜中8种元素均值为0~2.5 mg·kg^(-1),其中Zn平均含量最高为2.5 mg·kg^(-1),Hg未检出;各元素的内梅罗综合和单因子污染指数均小于0.7。18个市县蕹菜各元素平均含量均低于限值;海南市售蕹菜并未被重金属污染,均为合格蔬菜,属于食品安全水平。本研究可为海南食品安全风险提供数据支撑及参考,同时可为海南市售蕹菜的种植和食用提供指导。

浮床空心菜对罗非鱼养殖池塘水体微生态环境影响方式分析

探究浮床空心菜种植对罗非鱼养殖池塘水体微生态环境的影响方式,采用10%的浮床覆盖率进行空心菜种植作为处理塘,在空心菜旺盛生长以后,分别采集池塘水、对照塘水和空心菜根系样品,提取样品DNA,一部分进行细菌16S rRNA基因PCR扩增和高通量测序,研究其细菌群落结构,分析浮床空心菜对水中细菌群落结构的影响,分析空心菜根系和所在水中细菌群落结构的关系,另一部分采用荧光定量PCR方法测定固氮酶基因拷贝数,分析浮床空心菜对水体固氮酶基因的影响。结果表明,浮床空心菜种植对水中浮游细菌群落结构的直接影响不显著,空心菜根系生物膜作为池塘微生态环境重要组成部分发挥作用。空心菜根系生物膜还同时增加了池塘单位水体固氮微生物的数量。

不同水肥供应量及施用方式对菠菜产量和品质的影响

【目的】针对蔬菜生产中水肥过量供应造成水肥利用率过低且污染环境的问题,以菠菜为材料,研究使用太阳辐射量灌溉控制仪进行水肥管理时,不同水肥供应量对菠菜产量及品质的影响,以期为高效生产优质叶菜类蔬菜的水肥供应方式及供应量提供理论依据与技术支撑。【方法】试验使用太阳辐射量灌溉控制仪进行水肥管理,当太阳辐射量累积值达到设定阈值时会进行定量灌溉,通过该仪器设置4个处理(W1处理低水肥、W2处理中水肥、W3处理高水肥、W4处理中水无肥)和对照W5处理(传统栽培)共5个处理,研究不同水肥量及水肥施用方式对菠菜产量和品质的影响。【结果】W5处理的株高和产量都低于W2处理和W3处理,硝酸盐量、栽培后土壤中NO_(3)^(-)-N量和土壤EC值在所有处理中最高。W1处理和W4处理的株高及产量在所有处理中最低,其中W4处理的硝酸盐量、栽培后土壤中NO_(3)^(-)-N量和土壤EC值在所有处理中最低。W2处理和W3处理的株高和产量都是所有处理中最高的,W2处理和W3处理之间的株高和产量差异不显著,而W3处理的水肥供应量是W2处理的1.4倍,且W3处理叶片内硝酸盐量是W2处理的1.4倍且差异显著。【结论】使用太阳辐射量灌溉控制仪进行菠菜栽培时,水肥供应方案以W2处理为宜。

富氢水处理对菠菜采后贮藏品质的影响

以“帝沃9号”菠菜为试材,采用20%浓度富氢水处理菠菜10 min,(20±1)℃的冷库(相对湿度85%~90%)中贮藏5 d,研究了贮藏期间菠菜感官品质、营养品质及抗氧化酶活性等多项指标的变化,以期为富氢水在菠菜采后贮藏保鲜提供参考依据。结果表明:富氢水处理可以有效维持菠菜贮藏期间的感官品质,降低菠菜的失重率,抑制呼吸强度和乙烯释放量的上升,延缓可溶性固形物、叶绿素和维生素C含量的损失,同时抑制脂氧合酶(LOX)活性,降低相对电导率和丙二醛含量的积累,提高过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)活性。综上可知,富氢水处理可以明显延缓菠菜品质劣变。

蕹菜溃疡病菌分子检测方法的建立及田间监测

【目的】蕹菜是我国南方重要的经济作物,近年来随着蕹菜种植面积不断扩大,由穿孔黄单胞菌(Xanthomonas perforans)引起的蕹菜溃疡病日趋严重,对生产造成了巨大损失。建立高效快捷的蕹菜溃疡病菌检测技术,可为有效防控病害奠定基础。【方法】采用普通PCR检测技术,针对蕹菜溃疡病菌X. perforans基因组中特有序列TC2-1_002562(编码噬菌体终止酶大亚基家族蛋白)和TC2-1_002580(编码噬菌体家族蛋白)设计两对特异性检测引物,在同一个PCR体系中达到了快速检测蕹菜溃疡病菌的目的。【结果】建立的PCR检测方法可操作性强,对蕹菜溃疡病菌具有良好的特异性。利用特异性引物对来自广东多个地区的蕹菜植株、土壤和水体进行病原菌分子检测,发现第一批样本仅在5份来自东莞的蕹菜叶片上检测到病原菌,第二批样本分别在土壤、水体和植株上检测到病原菌。【结论】所建立的PCR检测方法能快速检测穿孔黄单胞菌,可用于对蕹菜溃疡病的早期诊断。该病在东莞、深圳等地呈普遍发生态势,田间检测结果表明,病害发展迅速,留种蕹菜种苗或种子很可能是该病的初侵染源,种植环境的水、土壤也是病害循环的重要环节,这对于今后进一步研究病害循环规律、制定针对性防控策略具有重要意义。

方志所见明清福建地区蕹菜的种植及其多样性特点

明清时期福建蕹菜种植区域广泛,具有多样性的特点。本文主要以福建旧志为主体史料,梳理志书中关于明清时期福建蕹菜的种植情况,并从蕹菜的培育、利用、文化等角度分析其多样性特点。

施用鸡粪和猪粪对2种土壤As、Cu和Zn有效性的影响

在水稻土和赤红壤中分别以质量分数2%和4%施入含As、Cu和Zn的鸡粪和猪粪，以不施肥为对照（CK）进行通菜盆栽试验，研究施入鸡、猪粪对土壤As、Cu和Zn有效性的影响.结果表明，施用鸡、猪粪几乎均比CK显著提高通菜地上部生物量，而且水稻土中生物量显著高于赤红壤.施用粪肥显著提高通菜As含量和As吸收量，呈高量处理〉低量处理、猪粪〉鸡粪处理且在水稻土〉赤红壤的规律.除水稻土中Cu含量外，施用粪肥也显著提高通菜Cu、Zn含量及吸收量.通菜收获后，所有处理土壤总As含量比试验前稍微降低、有效As含量及有效As占总As质量分数则大幅下降，但几乎所有粪肥处理土壤Cu和Zn的总含量、有效含量及有效质量分数均提高.与CK相比，粪肥处理土壤总As、有效As分别提高0.3～3.0 mg·kg^-1和0.011～0.034 mg·kg6-1，有效As质量分数增加0.033～0.178个百分点;总Cu、有效Cu提高3.1～30.4 mg·kg^-1和5.2～19.4 mg·kg^-1，有效Cu质量分数增加1.2～34.1个百分点;土壤总Zn、有效Zn提高-10.6～79.6 mg·kg^-1和4.0～65.9 mg·kg^-1，有效Zn质量分数增加1.0～64.2个百分点。如以土壤重金属有效含量增量及有效质量分数提高来评价其有效性变化，则粪肥提高土壤As、Cu和Zn有效性的作用为高量处理〉低量处理且在赤红壤中作用大于水稻土。

光线照射下芫荽和蕹菜常温贮藏效果比较

比较了芫荽(Coriandrum sativum L.)和蕹菜(Ipomoea aquatica Forsk)在20±1℃下光照处理的贮藏效果。在4d贮藏期内,用光合量子通量密度(PPED)为5μmol/m2·s的红光每天连续照射24h。结果表明,与黑暗条件下芫荽和蕹菜贮藏效果相比,光照有利于累积还原糖和减少叶绿素和VC损失,并且光照条件下蕹菜的贮藏效果好于芫荽;贮藏结束时,光照处理的芫荽和蕹菜中叶绿素含量分别比同期黑暗处理的高出76.82%和93.36%,还原糖含量分别高出32.69%和20.57%,VC保存率分别高出2.31和2.38倍;芫荽根部和蕹菜嫩茎切口吸收水分而使其保持鲜嫩状态,两者含水量变化与光照无关。

浮床栽培空心菜对罗非鱼养殖池塘水体中氮和磷的控制

总氮和总磷一直被认为是引起水体富营养化的重要因子,而氨氮和亚硝酸盐氮是养殖过程中引起鱼类疾病的关键环境因子。此试验利用PVC管构建浮床,研究了浮床栽培空心菜对罗非鱼养殖池塘水体中N和P的控制效果。数据表明,在试验后期,池塘水体中总氮水平降至淡水养殖池塘废水排放二级标准,而总磷水平达到地表水环境质量二类标准,氨氮的水平控制在1mg/L以下,而亚硝酸盐氮水平则控制在0.1mg/L以下。从各处理组对污染物的去除情况来看,空心菜种植时间与种植面积均与N、P的去除效果呈现较好的正相关关系,种植时间越长(>60天),种植面积与去除效果的正相关性越明显。结果表明,在集约化养殖池塘中采用浮床栽培空心菜能够对氮和磷实现有效的控制,并且空心菜浮床覆盖率为20%时比10%和15%处理组更具有经济效益。该试验为淡水池塘罗非鱼的健康养殖提供了一个新的思路。