Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria.
Appl Microbiol Biotechnol. 2017 Oct;101(19):7335-7346. doi: 10.1007/s00253-017-8447-6. Epub 2017 Aug 8.
Herein, we present a workflow for the development of talc-based microbial inoculants for foliar spray consisting of four steps. These include together with decision-making criteria (1) the selection of additives based on their capability to wet juvenile maize leaves, (2) their adhesion on the plant, (3) their interaction with the biological systems, and (4) the choice of thickener for good dispersion stability. In total, 29 additives including polysaccharides and proteins, polyols, glycosides, oils, waxes, and surfactants (e.g., chitosan, gelatin, glycerol, saponin, castor oil, polyethylene, rhamnolipid) were evaluated. Contact angle and spreading index measurements revealed that the use of 5% Geloil, 1% rhamnolipid, or suitable combinations of Geloil + rhamnolipid and Nurture Yield S 2002 + rhamnolipid enhanced wetting of hydrophobic maize leaves and adherence, similarly to the commercial wetting agents recommended for plant protection 1% Prev B2 and 1% Trifolio S Forte. Interaction of additives with biological systems was based on biocompatibility and phytotoxicity assays, and cell viability monitoring using the endophytic Gram-negative bacterium Paraburkholderia phytofirmans PsJN. Results from biocompatibility assays indicated that in contrast to rhamnolipid and Prev B2 Geloil, Nurture Yield S 2002 and Trifolio S Forte fully supported bacterial growth within a concentration range of 1 to 5%. Dose-dependent phytotoxicity was observed in plants treated with rhamnolipid. Most efficient formulation was composed of PsJN, talc, xanthan, and Geloil. Beyond that, the proposed workflow is expected to generally provide guidance for the development of spray formulations and help other researchers to optimize their choices in this area.
在此，我们提出了一个基于滑石粉的叶面喷施微生物接种剂的开发工作流程，该流程包括四个步骤。这些步骤包括（1）根据添加物润湿幼年玉米叶片的能力、（2）它们在植物上的附着力、（3）它们与生物系统的相互作用以及（4）选择增稠剂以获得良好的分散稳定性来选择添加剂，同时还包括决策标准。总共评估了 29 种添加剂，包括多糖和蛋白质、多元醇、糖苷、油、蜡和表面活性剂（例如壳聚糖、明胶、甘油、皂苷、蓖麻油、聚乙烯、鼠李糖脂）。接触角和铺展指数测量表明，使用 5%Geloil、1%鼠李糖脂或 Geloil+鼠李糖脂和 Nurture Yield S 2002+鼠李糖脂的合适组合可增强疏水性玉米叶片的润湿和附着力，类似于推荐用于植物保护的商业润湿剂 1%Prev B2 和 1%Trifolio S Forte。添加剂与生物系统的相互作用基于生物相容性和植物毒性测定以及使用内生革兰氏阴性细菌 Paraburkholderia phytofirmans PsJN 进行的细胞活力监测。生物相容性测定的结果表明，与鼠李糖脂和 Prev B2 相比，Geloil、Nurture Yield S 2002 和 Trifolio S Forte 在 1%至 5%的浓度范围内完全支持细菌生长。用鼠李糖脂处理的植物观察到剂量依赖性的植物毒性。最有效的配方由 PsJN、滑石粉、黄原胶和 Geloil 组成。除此之外，所提出的工作流程预计将为喷雾制剂的开发提供普遍指导，并帮助其他研究人员在该领域优化他们的选择。
