VEGETATIVE GROWTH AND DEVELOPMENT OF Mikania micrantha IN TARO AND CASSAVA PRODUCTION IN VITI LEVU, FIJI

A growth analysis study was conducted on Mikania micrantha Kunth stem sections grown between crop rows and at the edges of taro (Colocasia esculenta (L.) Schott) and cassava (Manihot esculenta Crantz) fields at Koronivia Research Station, Viti Levu Fiji. The relative stem growth rate of the longest stem of mikania in the taro field was 3.4 and 2.7 cm cm^-1 day^-1 at the edges and in between crop rows, respectively. While in the cassava field, the relative stem growth rate was 2.7 and 3.8 cm cm^-1 day^-1 for between crop rows and at the edges, respectively. Mikania plants growing at the edges of the field had greater relative leaf, stem and root dry matter growth rates than plants growing in between crop rows of both crops. These differences in plant performance may be attributed to the photosynthetically active radiation (PAR) that was available for interception at the edges of the crop but less so within the crop as well as a greater nutrient availability at the edges compared to between the crop rows.