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Biology subjects

Campbell, S. M.

Publications and source records attributed to Campbell, S. M..

2 recordsLinked to original sources

Substrate Temperature and Seed Scarification on Germination Parameters of Butterfly Pea (Clitoria ternatea)

Recent interest in the cultivation and use of butterfly pea (Clitoria ternatea) has increased demand for its commercial production. Successful germination of seed is a critical first step to its production; however, few studies have documented factors influential to germination success. To help support commercial production efforts, the influence of substrate temperature and seed scarification technique on germination parameters were evaluated. Two scarification (nicked and nicked and soaked) and three substrate temperature treatments (21, 24, and 27 {degrees}C) were imposed on C. ternatea seed. Following treatments, six germination parameters were recorded. Data showed seeds maintained at a substrate temperature of 21 {degrees}C reached maximal germination (54.8%) at the longest mean germination time (2.61 d) and slowest mean germination rate (0.39 d-1). Mechanical scarification by nicking the seed coat with a razor blade prior to soaking the seed for 24 hours reached maximal germination (80.95%) at the lowest mean germination time (2.06 d) and fastest mean germination rate (0.51 d-1). Optimal germination was attained when seed was scarified and soaked and then germinated in rockwool substrate maintained at a temperature (To) of 21 {degrees}C. Results provide commercial growers with production technique information helpful to fast and efficient germination of C. ternatea seed.

plant biology↗

Evaluation of substrate composition and exogenous hormone application on vegetative propagule rooting success of essential oil hemp (Cannabis sativa L.)

To support the rapidly expanding industrial hemp industry, a commercial supply of high-quality starter plants with low genetic variability from nurseries will be key to consistent and efficient cultivation efforts. Rooting success was evaluated across four propagation medias, five rooting hormones, and eight commercially available high-cannabidiol (CBD) essential oil hemp cultivars. Cuttings were placed in a climate-controlled room and assessed for rooting success 12 days after cloning. Rooting success was determined by quantifying total root number, cumulative total root length, and total root mass. Propagation media had the greatest effect on rooting success (13-80 %). Rockwool had the highest rooting success resulting in 10-fold increases in rooting traits over the next highest scoring medium (Berger BM6). Hormone applications significantly improved (15-to 18-fold) rooting success compared to no hormone application, while non-statistical differences were observed across auxin hormone concentrations and application methods. Genetic variation in rooting response was observed between cultivars with Cherry Wine outperforming all other cultivars with an approximate 20% increase in rooting success over the next highest rooting cultivar, Wife. Although the ideal combination was not specifically identified in this study, findings provide insight into how rooting hormone application and medium selection impact vegetative propagule rooting success of essential oil hemp.

plant biology↗