Dodder occurrence and management using vinegar-based solutions at Makerere University.

Abstract

Dodder (Cuscuta spp.), a notorious parasitic plant, has become a significant threat to ornamental plants majorly golden dewdrop in Uganda. The weed's parasitic activity disrupts the aesthetic appeal, growth, and functionality of ornamental landscapes, which is of great concern given the horticultural industry's substantial contribution to Uganda's GDP. Despite various control efforts, the invasive weed's spread remains unchecked, and conventional methods such as hand weeding and glyphosate application pose challenges. The use of glyphosate, whilst effective, carries risks to the environment and causes systemic death of ornamental plants. Vinegar, as an organic herbicide, is considered an appropriate choice due to its minimal impact on the root system of plants. This study aimed at exploring the potential of vinegar-based solutions as a safer, more effective, and environmentally friendly alternative for controlling dodder infestation. Specifically, prevalence of the weed at Makerere University main campus was established. The efficacy of vinegar in management of the dodder was equally investigated. The treatments included 10%, 20%, and 30% vinegar concentrations and water as a control. OSHO starter and NPK 19:19:19 fertilizers were also applied to rejuvenate the plants. The results showed that dodder was most prevalent in the northern part of the campus and seemed to thrive under partial shade, with Duranta spp. as the most affected host. Of the three concentrations, the vinegar-based solution, the higher concentration of 30% v/v was most effective in managing the weed by causing it to wilt and die. The 30% treatment caused 96% success compared to 92% and 90% of 20% and 10% vinegar treatments respectively under full sun. Full sun treatments performed better than those of partial sun after 2 weeks with 78.6% and 74% respectively. OSHO induced faster recovery with an average of 5 days compared with 6 days of NPK. In conclusion, this study establishes vinegar as an effective means of controlling dodder, especially at the higher concentration of 30%, offering a safer alternative to conventional methods. The use of OSHO fertilizer further enhances recovery times. These findings contribute valuable insights into the management of dodder in ornamental landscapes, with implications for sustainable horticulture practices.