Nordstedt Nathan P, Chapin Laura J, Taylor Christopher G, Jones Michelle L
Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH, United States.
Department of Plant Pathology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH, United States.
Front Plant Sci. 2020 Jan 28;10:1754. doi: 10.3389/fpls.2019.01754. eCollection 2019.
The sustainability of ornamental crop production is of increasing concern to both producers and consumers. As resources become more limited, it is important for greenhouse growers to reduce production inputs such as water and chemical fertilizers, without sacrificing crop quality. Plant growth promoting rhizobacteria (PGPR) can stimulate plant growth under resource-limiting conditions by enhancing tolerance to abiotic stress and increasing nutrient availability, uptake, and assimilation. PGPR are beneficial bacteria that colonize the rhizosphere, the narrow zone of soil in the vicinity of the roots that is influenced by root exudates. In this study, experiments were utilized to screen a collection of 44 strains for their ability to withstand osmotic stress. A high-throughput greenhouse experiment was then utilized to evaluate selected strains for their ability to stimulate plant growth under resource-limiting conditions when applied to ornamental crop production systems. The development of a high-throughput greenhouse trial identified two pseudomonads, 29G9 and 90F12-2, that increased petunia flower number and plant biomass under drought and low-nutrient conditions. These two strains were validated in a production-scale experiment to evaluate the effects on growth promotion of three economically important crops: × , , and × . Plants treated with the two bacteria strains had greater shoot biomass than untreated control plants when grown under low-nutrient conditions and after recovery from drought stress. Bacteria treatment resulted in increased flower numbers in drought-stressed and . In addition, bacteria-treated plants grown under low-nutrient conditions had higher leaf nutrient content compared to the untreated plants. Collectively, these results show that the combination of and greenhouse experiments can efficiently identify beneficial strains that increase the quality of ornamental crops grown under resource-limiting conditions.
观赏作物生产的可持续性日益受到生产者和消费者的关注。随着资源变得更加有限，对于温室种植者来说，在不牺牲作物质量的情况下减少水和化肥等生产投入非常重要。植物促生根际细菌（PGPR）可以通过增强对非生物胁迫的耐受性以及提高养分的有效性、吸收和同化作用，在资源有限的条件下刺激植物生长。PGPR是定殖于根际的有益细菌，根际是受根系分泌物影响的根部附近狭窄的土壤区域。在本研究中，通过实验筛选了44株菌株的耐渗透胁迫能力。然后利用高通量温室实验来评估所选菌株在应用于观赏作物生产系统时，在资源有限条件下刺激植物生长的能力。高通量温室试验的开展确定了两种假单胞菌，29G9和90F12 - 2，它们在干旱和低养分条件下增加了矮牵牛的花数和植株生物量。在一项生产规模的实验中对这两种菌株进行了验证，以评估它们对三种经济上重要的作物（×、和×）生长促进的影响。在低养分条件下生长以及从干旱胁迫恢复后，用这两种细菌菌株处理的植物比未处理的对照植物具有更大的地上部生物量。细菌处理使干旱胁迫下的和的花数增加。此外，与未处理的植物相比，在低养分条件下生长的经细菌处理的植物叶片养分含量更高。总体而言，这些结果表明，结合和温室实验能够有效地鉴定出在资源有限条件下提高观赏作物品质的有益菌株。
