Enhancing Rooting of Vegetatively Propagated Cannabis sativa ‘BaOx’ Cuttings

Hemp (Cannabis sativa L.) has recently become legalized in the United States (U.S.). To grow hemp, often propagation occurs via asexual means through rooting vegetative tip cuttings. To produce plants, meristems are excised from stock plants and propagated to produce transplants for greenhouse or field-production. Successfully rooting vegetative cuttings can vary widely among growers due to greenhouse propagation environmental conditions, cultural inputs and practices, and vegetative cutting quality. To overcome rooting challenges, the impact of cutting stem caliper (diameter) and the use of root-zone heating (RZH) on rhizogenesis were investigated. Results indicated that large (2.9 – 3.2 mm) caliper cuttings and the use of RZH of 27.8oC resulted in a higher quality rooted cutting

Magnesium’s Impact on Cannabis sativa ‘BaOx’ and ‘Suver Haze’ Growth and Cannabinoid Production

Limited research exists on the fertility needs for industrial hemp (Cannabis sativa) and the impact of fertility on plant growth and cannabinoids. Optimizing floral production for cannabinoid production and especially cannabidiol (CBD) production, is an economic goal for growers. Magnesium (Mg) is an essential nutrient for plant growth and plays many key roles in plant growth and when deficient leads to suboptimal plant growth. Six Mg fertility rates (0.0, 12.5, 25.0, 50.0, 75.0, and 100.0 mg·L-1) were evaluated to determine the optimal fertility for C. sativa on two High CBD-type cultivars ‘BaOx; and ‘Suver Haze’. Foliar Mg concentrations increased linearly for all life stages with the greatest foliar Mg concentrations being in the highest rate of 100.0 mg·L-1 Mg. Of the six rates, 50.0 and 75.0 mg·L-1 Mg optimized plant height, diameter, and plant total dry weight as well as having similar cannabinoid concentrations

The Impacts of Micronutrient Fertility on the Mineral Uptake and Growth of Brassica carinata

Many abiotic factors impact the yield and growth of Brassica carinata (commonly referred to as carinata or Ethiopian mustard). Very little is known about carinata and how mineral nutrients impact its growth, and more specifically, the sufficiency values for fertility over the plant’s growth cycle and life stages. This study explored the impacts that plant nutrients, specifically micronutrients, can have on the growth and development of carinata over its distinct life stages (rosette, bolting, flowering, and pod set). Plants were grown under varying micronutrient concentrations (0, 25, 50, 75, 87.5, and 100%) of a modified Hoagland’s solution. Data were collected on plant height, canopy diameter, leaf tissue mineral nutrient concentrations, and biomass. The results demonstrated that micronutrient fertility has profound impacts on the production of Brassica carinata during different life stages. Boron (B) exclusion had the greatest impact on the growth and reproduction of Brassica carinata, with the death of the apical meristem that resulted in a lack of siliques or seeds at the lowest rate. Optimal relative elemental leaf tissue concentrations varied among micronutrient fertility concentrations and life stages. Certain elements exhibited linear increases in nutrient leaf tissue accumulation as solution concentration increased without reaching a maximum concentration during specific life stages. Other life stages and/or elements produced distinct plateau leaf tissue mineral concentrations despite increasing fertility treatment concentrations such as B in the rosette stage (47.2–50.0 mg·kg−1), copper (Cu) (bolting stage at 6.62–7.57 mg·kg−1), zinc (Zn) (bolting stage at 27.47–39.87 and flowering at 33.98–43.50 mg·kg−1), molybdenum (Mo) (flowering stage at 2.42–3.23 mg·kg−1), and manganese (Mn) (bolting stage at 117.03–161.63 mg·kg−1). This work demonstrates that Brassica carinata has different fertility demands and will accumulate differing leaf tissue concentrations during its life stages. This work serves as a baseline for further uptake and portioning work for Brassica carinata

Prioritizing Out-of-Care Case Investigations in King County, Washington

Thesis (Master's)--University of Washington, 2023Background: Health departments need to investigate cases of people with HIV who appear to be out of care butoften have insufficient resources to investigate all cases and need a way to prioritize investigations. Methods: In this retrospective cohort analysis, we used classification and regression tree (CART) methodologyto develop and validate a decision algorithm for indicating which HIV cases need investigation. The goal is that this algorithm could be used prospectively to confirm out-of-care status and offer assistance relinking to care. The data utilized is from Public Health – Seattle King County’s Comprehensive HIV/AIDS Database (CHARD) which is used to manage HIV case investigations. A “priority” designation is applied to investigations where 1.) the individual was confirmed to be out of care and had been successfully contacted or 2.) the individual was confirmed to be out of care and could not be contacted. We considered 20 potential predictors for priority designation relevant to patient demographics, laboratory result patterns, and reported investigation characteristics. We compared the test characteristics of an optimized algorithm and simple algorithm. Results: During 01/2018 – 12/2022, 4,311 HIV cases were referred for further investigation. Across thevalidation data, the optimized and simplified algorithms correctly identified 79.9% and 81.3% of priority investigations, respectively. The optimized algorithm had the lowest specificity at 88.0% and the simplified algorithm had the highest specificity at 89.0%. Models did not perform significantly worse across gender, age, and racial ethnic strata except for when applied to Non-Hispanic Asians (poor positive predictive value) and Non-Hispanic Native Hawaiians/Pacific Islanders (poor negative predictive value). Conclusions: We found that the performance of two algorithms (one optimized and one simplified) developed withCART were effective in identifying non-priority investigations and could be used prospectively to triage case investigations