{"title":"Toxic and non-toxic cyanobacterial biomass as a resource for sustainable agriculture: A lettuce cultivation experiment","authors":"","doi":"10.1016/j.envres.2024.119942","DOIUrl":null,"url":null,"abstract":"<div><p>Cyanobacteria represent a promising resource for sustainable agriculture, as they have demonstrated the ability to restore soil fertility even after death and decay. However, several cyanobacteria can also release secondary metabolites, such as cyanotoxins, which may compromise the quality of agricultural products and pose a potential risk to human health. Depending on the concentration of exposure, few studies reported deleterious effects on plant species when irrigated with cylindrospermopsin (CYN) contaminated water, impairing plant growth and leading to food product contamination, while other studies show promoting effects on plant yield. To evaluate the potential of cyanobacterial biomass (cyanotoxin-containing or not) as a sustainable resource for soil amendment, biostimulants or fertilizers for lettuce cultivation, a study was carried out that consisted of the culture of lettuce plants under controlled conditions, in soil: (1) with no extra nutrient addition (control) and supplemented with 0.6 g of freeze-dried <em>Raphidiopsis raciborskii</em> biomass of (2) a non-CYN-producing strain, (3) a CYN-producing strain, and (4) the same CYN-producing strain pasteurized. Results showed no significant differences in photosystem II efficiency with the amendment addition. On the contrary, shoot fresh weight significantly increased in lettuce plants grown with the cyanobacterial biomass addition, especially in condition (3). In addition, there were significant differences in mineral concentrations in lettuce leaves after the cyanobacterial biomass addition, such as K, Na, Ca, P, Mg, Mn, Zn, Cu, Mo, and Co. CYN accumulation was detected under conditions (3) and (4), with concentrations observed in descending order from roots > soil > shoot. Nevertheless, the CYN concentration in edible tissues did not exceed the WHO-proposed tolerable daily intake of 0.03 μg/kg/day. These findings suggest that incorporating cyanobacterial biomass as a soil amendment, biostimulant or fertilizer for lettuce cultivation, even with trace amounts of CYN (1–40 μg/g), may enhance plant yield without leading to cyanotoxin accumulation in edible tissues above the WHO-recommended tolerable daily intake.</p></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":null,"pages":null},"PeriodicalIF":7.7000,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0013935124018474/pdfft?md5=ddf7dbb769c7674873727a978f70be50&pid=1-s2.0-S0013935124018474-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Research","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0013935124018474","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Cyanobacteria represent a promising resource for sustainable agriculture, as they have demonstrated the ability to restore soil fertility even after death and decay. However, several cyanobacteria can also release secondary metabolites, such as cyanotoxins, which may compromise the quality of agricultural products and pose a potential risk to human health. Depending on the concentration of exposure, few studies reported deleterious effects on plant species when irrigated with cylindrospermopsin (CYN) contaminated water, impairing plant growth and leading to food product contamination, while other studies show promoting effects on plant yield. To evaluate the potential of cyanobacterial biomass (cyanotoxin-containing or not) as a sustainable resource for soil amendment, biostimulants or fertilizers for lettuce cultivation, a study was carried out that consisted of the culture of lettuce plants under controlled conditions, in soil: (1) with no extra nutrient addition (control) and supplemented with 0.6 g of freeze-dried Raphidiopsis raciborskii biomass of (2) a non-CYN-producing strain, (3) a CYN-producing strain, and (4) the same CYN-producing strain pasteurized. Results showed no significant differences in photosystem II efficiency with the amendment addition. On the contrary, shoot fresh weight significantly increased in lettuce plants grown with the cyanobacterial biomass addition, especially in condition (3). In addition, there were significant differences in mineral concentrations in lettuce leaves after the cyanobacterial biomass addition, such as K, Na, Ca, P, Mg, Mn, Zn, Cu, Mo, and Co. CYN accumulation was detected under conditions (3) and (4), with concentrations observed in descending order from roots > soil > shoot. Nevertheless, the CYN concentration in edible tissues did not exceed the WHO-proposed tolerable daily intake of 0.03 μg/kg/day. These findings suggest that incorporating cyanobacterial biomass as a soil amendment, biostimulant or fertilizer for lettuce cultivation, even with trace amounts of CYN (1–40 μg/g), may enhance plant yield without leading to cyanotoxin accumulation in edible tissues above the WHO-recommended tolerable daily intake.
蓝藻是一种很有前景的可持续农业资源,因为它们即使在死亡和腐烂后仍能恢复土壤肥力。然而,一些蓝藻也会释放次生代谢物,如蓝藻毒素,这可能会影响农产品的质量,并对人类健康构成潜在风险。根据接触浓度的不同,有少数研究报告称,用受圆柱孢藻毒素(CYN)污染的水进行灌溉会对植物物种产生有害影响,损害植物生长并导致食品污染,而其他研究则表明,蓝藻毒素对植物产量有促进作用。为了评估蓝藻生物质(无论是否含有蓝藻毒素)作为土壤改良剂、生物刺激剂或莴苣栽培肥料的可持续资源的潜力,我们开展了一项研究,包括在受控条件下在土壤中培养莴苣植株:(1)不添加额外养分(对照),并在土壤中添加 0.6 克冻干的 Raphidiopsis raciborskii 生物质,(2) 非 CYN 生产菌株,(3) CYN 生产菌株,(4) 经过巴氏灭菌处理的相同 CYN 生产菌株。结果表明,添加添加剂后,光系统 II 的效率没有明显差异。相反,添加蓝藻生物量的莴苣植株的嫩枝鲜重明显增加,尤其是在条件(3)下。此外,添加蓝藻生物质后,莴苣叶片中的矿物质浓度(如 K、Na、Ca、P、Mg、Mn、Zn、Cu、Mo 和 Co)也有明显差异。在条件(3)和条件(4)下检测到 CYN 的积累,浓度依次为根部 > 土壤 > 嫩芽。不过,可食用组织中的 CYN 浓度并未超过世界卫生组织规定的每日可容忍摄入量(0.03 μg/kg/日)。这些研究结果表明,将蓝藻生物质作为土壤改良剂、生物刺激剂或肥料用于莴苣栽培,即使含有微量的 CYN(1∼40 μg/g),也可提高植物产量,而不会导致可食用组织中的蓝藻毒素积累超过世界卫生组织建议的每日耐受摄入量。
期刊介绍:
The Environmental Research journal presents a broad range of interdisciplinary research, focused on addressing worldwide environmental concerns and featuring innovative findings. Our publication strives to explore relevant anthropogenic issues across various environmental sectors, showcasing practical applications in real-life settings.