Victor Maddox

Activities and Prevalence of Proteobacteria Members Colonizing Echinacea purpurea Fully Account for Macrophage Activation Exhibited by Extracts of This Botanical

Evidence supports the theory that bacterial communities colonizing Echinacea purpurea contribute to the innate immune enhancing activity of this botanical. Previously, we reported that only about half of the variation in in vitro monocyte stimulating activity exhibited by E. purpurea extracts could be accounted for by total bacterial load within the plant material. In the current study, we test the hypothesis that the type of bacteria, in addition to bacterial load, is necessary to fully account for extract activity. Bacterial community composition within commercial and freshly harvested (wild and cultivated) E. purpurea aerial samples was determined using high-throughput 16S rRNA gene pyrosequencing. Bacterial isolates representing 38 different taxa identified to be present within E. purpurea were acquired, and the activity exhibited by the extracts of these isolates varied by over 8000-fold. Members of the Proteobacteria exhibited the highest potency for in vitro macrophage activation and were the most predominant taxa. Furthermore, the mean activity exhibited by the Echinacea extracts could be solely accounted for by the activities and prevalence of Proteobacteria members comprising the plant-associated bacterial community. The efficacy of E. purpurea material for use against respiratory infections may be determined by the Proteobacterial community composition of this plant, since ingestion of bacteria (probiotics) is reported to have a protective effect against this health condition.

Maximizing 'Cimarron' Little Bluestem Establishment as Secondary Rough for a Golf Course

Native grasses are an important design component in secondary roughs of golf courses due to minimal maintenance requirements and aesthetics. However, problems with seed germination and subsequent establishment limit their use. Two 2-year studies on ‘Cimarron’ little bluestem were conducted in 2000 and 2002 at Mississippi State University. In each study, seed was planted at five rates: 12.7, 25.4, 38.1, 51, and 63.4 lb of pure live seed (PLS) per acre. Visual percent cover was recorded each month after planting (MAP). The seeding rate of 12.7 lb PLS/acre may not be acceptable for secondary roughs, since coverage was only 6.7 and 4%, respectively, at 2 MAP. This would most likely result in establishment failure during rainfall events. By the end of the first 2-year trial, there were no significant differences among coverage rates ≥ 25.4 lb PLS/acre. By the end of the second 2-year study, there was no difference among seeding rates. Based upon this study, rates at or above 25.4 lb PLS/acre would be recommended. Though these higher ‘Cimarron’ seeding rates benefit first year establishment, 100% cover is still unlikely and establishment will require a minimum of 2 years. Early management response to weed competition may be a key component for successful establishment of ‘Cimarron’ little bluestem in golf course secondary roughs.