ASHS 2024 Conference

Producing sweetpotatoes involve several phases presenting unique challenges, most notably during transplanting. Sweetpotato slips, used for asexual reproduction, have non-uniform characteristics, making transplanting difficult. Additionally, the transition from a greenhouse to a field condition poses environmental risks and challenges, resulting in low transplant survival rates. A high slip mortality rate creates economic and logistical problems for producers. Plant growth regulators (PGRs) have been found to induce lignification or thickening of cell walls, which can alleviate environmental stresses in other crops; however, their impact remains unexplored in sweetpotato slips. Therefore, a study at Mississippi State University was conducted with the primary goal to enhance sweetpotato slip quality and improve transplant establishment rates. The study involves two greenhouse trials to identify the most effective PGR types and concentrations, and two histology trials to illustrate the effects of PGRs on sweetpotato slip lignin and cell wall. The greenhouse trials utilize a randomized complete block design to assess four different PGR types and thirteen concentrations on three replications of sweetpotato slips with 38 subsamples per treatment per replication. Data on plant height, stem diameter, number of nodes, SPAD, leaf area, and dry weight and fresh weight of the slips and roots were collected to determine the effects of PGRs on the plants. The histology trials included the same PGR treatments and concentrations to the slips. The slips were then collected, cross-sectioned, stained, and evaluated and measured under a microscope. The study proved that PGRs do have an effect on sweetpotato slips, by altering plant height, dry weight, and fresh weight, while not impacting the number of nodes. Thickening of the cell wall was also observed in slips treated with certain PGRs and it is hypothesized that this thickening of cell walls can contribute to reduced slip mortality when transplanting greenhouse produced slips to the field.