蓝细菌代表了可持续农业的有前途的资源,因为它们已经证明了即使在死亡和腐烂之后也能够恢复土壤肥力。然而,几种蓝藻还能释放次生代谢产物,如氰基毒素,这可能会损害农产品的质量,并对人类健康构成潜在风险。根据暴露的浓度,很少有研究报告对植物物种的有害影响,当用cylindrospermopsin(CYN)污染的水灌溉时,损害植物生长并导致食品污染,而其他研究表明对植物产量有促进作用。为了评估蓝细菌生物量(含或不含氰毒素)作为土壤改良剂的可持续资源的潜力,生菜种植的生物刺激剂或肥料,进行了一项研究,包括在受控条件下培养莴苣植物,在土壤中:(1)没有额外的养分添加(对照),并补充了(2)非CYN生产菌株的0.6g冻干的raphiopsisraciborskii生物量,(3)一株CYN生产菌株,和(4)对相同的CYN生产菌株进行巴氏灭菌。结果表明,添加修正剂的光系统II效率没有显着差异。相反,在添加蓝藻生物量的情况下,生菜植株的芽鲜重显着增加,特别是在条件(3)。此外,蓝藻生物量添加后,莴苣叶片中的矿物质浓度存在显着差异,比如K,Na,Ca,P,Mg,Mn,Zn,Cu,Mo,在条件(3)和(4)下检测到Co.CYN积累,浓度从根>土壤>芽降序观察。然而,可食用组织中的CYN浓度未超过WHO提出的0.03μg/kg/天的每日耐受摄入量。这些发现表明,将蓝细菌生物量作为土壤改良剂,生菜种植用生物刺激剂或肥料,即使有痕量的CYN(1~40μg/g),可能会提高植物产量,而不会导致可食用组织中的蓝藻毒素积累超过WHO推荐的每日摄入量。
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 cyanobacteria 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 producer strain, (3) a CYN producer strain, and (4) the same CYN producer 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.