Growth parameters, nutrient status and colonization density of beneficial microbes in winter rye grown organically and conventionally.

The study focuses on the impact of a beneficial microbial consortium on the plant performance of winter rye under different farming practices during the vegetation period, including the winter growing season. Winter rye plants grown in a long-time field trial (Thy_ABS; 52°15’ N, 13°14’ E, 44 m a.s.l.) under conventional or organic farming practices were inoculated after plant emergence in autumn 2020 with a beneficial microbial consortium containing Pseudomonas sp. (RU47, drench inoculation with 2 L per m² of 7.5 x 107 CFU mL-1), Bacillus atrophaeus (ABi03, drench inoculation with 2 L per m² of 7.5 x 107 CFU mL-1) and Trichoderma harzianum (OMG16, soil inoculation with 100 mg inoculum per m²). The density of the microbial inoculants in the rhizosphere and root-associated soil as well as the plant performance and nutrient status was quantified in autumn and the following spring. Selective plating demonstrated that the beneficial microbes successfully colonized the rhizosphere and root-associated soil of winter rye throughout its early growth cycle. The inoculation with a beneficial microbial consortium enhanced the biomass of winter rye, especially under organic farming practices at the second sampling in spring. The consortium significantly improved the nutrient status of the winter rye plants, providing an effective way to overcome nutrient limitations often found in organic farming. Research domain: Plant Cultivation and Agricultural Technology Research question: We hypothesized that (i) early inoculation of winter rye enables sufficient colonization of each BMc member at early plant developmental stage, supporting its persistence in the rhizosphere throughout the vegetation period; (ii) the application of BMc shapes the composition of the rhizosphere bacterial community depending on the farming practice and thus differentially affects the plant performance.本研究聚焦于有益微生物联合体（beneficial microbial consortium, BMc）对冬黑麦植株生长表现的影响，试验覆盖包括冬季生长期在内的整个植被期，设置不同耕作模式开展探究。 本试验依托长期田间定位试验（Thy_ABS；北纬52°15’，东经13°14’，海拔44米），分别采用常规耕作与有机耕作两种种植模式，于2020年秋季冬黑麦出苗后进行接种处理。所用有益微生物联合体包含以下菌株：假单胞菌属（Pseudomonas sp.，RU47菌株，以每平方米2升浓度为7.5×10^7 CFU·mL⁻¹的菌液灌根接种）、萎缩芽孢杆菌（Bacillus atrophaeus，ABi03菌株，以每平方米2升浓度为7.5×10^7 CFU·mL⁻¹的菌液灌根接种）以及哈茨木霉（Trichoderma harzianum，OMG16菌株，以每平方米100毫克菌剂进行土壤接种）。 分别于秋季及次年春季对根际与根围土壤中的微生物接种剂密度、植株生长表现及养分状况进行定量检测。选择性平板培养结果显示，有益微生物可在冬黑麦整个早期生长周期内成功定殖于其根际与根围土壤。 有益微生物联合体接种可提升冬黑麦的生物量，尤其在春季第二次采样时的有机耕作模式下效果显著。该联合体可有效改善冬黑麦植株的养分状况，为解决有机耕作中常见的养分限制问题提供了可行途径。 研究领域：植物栽培与农业技术。 研究假设：（i）冬黑麦早期接种可使各有益微生物成员在植株早期发育阶段完成充分定殖，保障其在整个植被期的根际留存能力；（ii）有益微生物联合体的施用会根据耕作模式改变根际细菌群落组成，进而对植株生长表现产生差异化影响。