Impact of the invasive cuscuta campestris on vegetative cover and plant biodiversity in Homa- bay county

Abstract

Purpose: This research paper focused on the impact of Cuscuta campestris on vegetative cover and plant biodiversity in Homa-Bay County. The specific objective was to investigate the impact on plant growth and development with indicator as photosynthetic capacity of preferred host plants and chlorophyll content and leaf weight as the parameters. Methodology: The study was conducted in hotspot areas of invasion, Rachuonyo North, Homa Bay town and Suba North using Completely Randomized Experimental Block Design. The data was collected through field observation and laboratory analysis. The study used descriptive and correlation data analysis procedures to show the impact on photosynthetic capacity, ANOVA to determine statistically significant differences among the obtained results for each parameter of the infected and uninfected samples. Variance analysis were conducted using SPSS 20 (IBM Corp. Armonk, NY, USA) and differences between means were tested by ANOVA. Values of P ≤ 0.05 were considered significantly different. Findings: The results showed that the invasion was more intense in Theveta peruvinia and Euphorbia tirucalli species. Mean leaf amounts of chlorophyll were observed to decline with chlorophyll a from 3.97 to 1.59 mg/g and chlorophyll b from 2.65 to 1.18 mg/g and total chlorophyll value from 6.62 to 2.76 mg/g on infection resulting to reduced photosynthetic efficiency and low organic material formation. Leaf wet and dry weight significantly decreased in both infected varieties. The mean wet weight of 17.61g in infected was significantly different, F (1, 4) = 235.74, p< .05, from the mean wet weight of 24.23g in the uninfected Yellow Oleander, while the mean dry weight of 5.55g in infected was significantly different, F (1, 4) = 159.72, p< .05, from the mean dry weight of 7.87g in the uninfected Yellow Oleander. Similarly, a significant difference, F (1, 4) = 714.64, p< .05, was observed in the Calliandra calothyrsus variety. These demonstrated how C. campestris is detrimental, causing ecological impacts with direct effects on plant biodiversity by reducing growth and development of infected host plants and even leading to death. Unique Contributions to Theory, Practice, and Policy: The paper recommends intense sensitization of the community on the impacts of dodder from the findings for an enhanced understanding and need for management and control. The findings are to be disseminated through workshops involving farmers, NGOs, and community based organizations, academic conferences, and publications to help create awareness of the impacts and mobilize the entire public on management and possible total eradication. Further research is needed to investigate on nutrient sources of attraction in the preferred host plants with the aim of finding a permanent solution for total eradication in order to restore the vegetative cover and plant biodiversity. Keywords: Cuscuta campestris, Thevetia peruviana, Euphorbia tirucalli, Calliandra calothyrsus, Impact, Chlorophyll content, Leaf mass, Vegetative cover and Plant Biodiversity