Alfonzetti Matthew, Doleac Sebastien, Mills Charlotte H, Gallagher Rachael V, Tetu Sasha
School of Natural Sciences, Macquarie University, Sydney, NSW 2109, Australia.
AirSeed Technologies Australia Pty Ltd., Sydney, NSW 2000, Australia.
Microorganisms. 2022 Dec 24;11(1):55. doi: 10.3390/microorganisms11010055.
Soil microbes play important roles in plant health and ecosystem functioning, however, they can often be disturbed or depleted in degraded lands. During seed-based revegetation of such sites there is often very low germination and seedling establishment success, with recruitment of beneficial microbes to the rhizosphere one potential contributor to this problem. Here we investigated whether Australian native plant species may benefit from planting seed encapsulated within extruded seed pellets amended with one of two microbe-rich products: a commercial vermicast extract biostimulant or a whole-soil inoculum from a healthy reference site of native vegetation. Two manipulative glasshouse trials assessing the performance of two Australian native plant species ( and ) were carried out in both unmodified field-collected soil (trial 1) and in the same soil reduced in nutrients and microbes (trial 2). Seedling emergence and growth were compared between pelleted and bare-seeded controls and analyzed alongside soil nutrient concentrations and culturable microbial community assessments. The addition of microbial amendments maintained, but did not improve upon, high levels of emergence in both plant species relative to unamended pellets. In trial 1, mean time to emergence of seedlings was slightly shorter in both amended pellet types relative to the standard pellets, and in trial 2, whole-soil inoculum pellets showed significantly improved growth metrics. This work shows that there is potential for microbial amendments to positively affect native plant emergence and growth, however exact effects are dependent on the type of amendment, the plant species, and the characteristics of the planting site soil.
土壤微生物在植物健康和生态系统功能中发挥着重要作用，然而，在退化土地中它们常常受到干扰或数量减少。在此类场地基于种子的植被恢复过程中，种子萌发率和幼苗定植成功率通常很低，有益微生物向根际的募集是导致这一问题的一个潜在因素。在这里，我们研究了澳大利亚本土植物物种是否会受益于播种包裹在挤压种子丸粒中的种子，这些丸粒用两种富含微生物的产品之一进行了改良：一种商业蚯蚓粪提取物生物刺激剂或来自本土植被健康参照场地的全土接种物。在未改良的田间采集土壤（试验1）和养分及微生物含量降低的同一种土壤（试验2）中，进行了两项评估两种澳大利亚本土植物物种（ 和 ）表现的可控温室试验。比较了丸粒种子和裸种对照之间的幼苗出土和生长情况，并结合土壤养分浓度和可培养微生物群落评估进行了分析。与未改良的丸粒相比，添加微生物改良剂维持了但并未改善两种植物物种的高出土率。在试验1中，相对于标准丸粒，两种改良丸粒类型中 幼苗的平均出土时间略短，而在试验2中，全土接种物丸粒的生长指标有显著改善。这项工作表明，微生物改良剂有可能对本土植物的出土和生长产生积极影响，然而确切效果取决于改良剂的类型、植物物种以及种植场地土壤的特性。
