University of Florida/Institute of Food and Agricultural Sciences Southwest Florida Research and Education Center, Immokalee, FL, 34142, USA.
GlaxoSmithKline US, Human Genetics, Collegeville, PA, 19426, USA.
Microb Ecol. 2020 Aug;80(2):398-409. doi: 10.1007/s00248-020-01497-7. Epub 2020 Mar 6.
There is increased interest by the agricultural industry in microbial amendments that leverage natural beneficial interactions between plants and soil microbes to improve crop production. However, translating fundamental knowledge from laboratory experiments into efficient field application often has mixed results, and there is less clarity about the interaction between added microbes and the native microbial community, where microorganisms belonging to the same phylogenic clades often reside. In this study, four commercially available microbial amendments were examined in two greenhouse experiments using field soil to assess their impact on tomato plant growth and the native soil microbial communities. The amendments contained different formulations of plant growth-promoting bacteria (Lactobacilli, Rhizobia, etc.), yeasts, and mycorrhizal fungi. The application of the tested amendments in greenhouse conditions resulted in no significant impact on plant growth. A deeper statistical analysis detected variations in the microbial communities that accounted only for 0.25% of the total species, particularly in native taxa not related to the inoculated species and represented less than 1% of the total variance. This suggests that under commercial field conditions, additional confounding variables may play a role in the efficacy of soil microbial amendments. This study confirms the necessity of more in-depth validation requirements for the formulations of soil microbial amendments before delivery to the agricultural market in order to leverage their benefits for the producers, the consumers, and the environment.
农业界越来越关注利用植物与土壤微生物之间的自然有益相互作用来提高作物产量的微生物改良剂。然而，将基础实验室实验知识转化为高效的田间应用往往结果喜忧参半，对于添加的微生物与本地微生物群落（通常存在同系发育枝系的微生物）之间的相互作用，人们的了解较少。在这项研究中，使用田间土壤在两个温室实验中检查了四种市售微生物改良剂，以评估它们对番茄植物生长和本地土壤微生物群落的影响。改良剂包含不同配方的植物促生细菌（乳杆菌、根瘤菌等）、酵母和菌根真菌。在温室条件下应用测试的改良剂对植物生长没有显著影响。更深入的统计分析检测到微生物群落的变化，仅占总物种的 0.25%，特别是与接种物种无关的本地分类群，占总方差的不到 1%。这表明，在商业田间条件下，其他混杂变量可能会影响土壤微生物改良剂的功效。本研究证实，在将土壤微生物改良剂推向农业市场之前，需要对其配方进行更深入的验证要求，以利用其为生产者、消费者和环境带来的好处。
