EFFECTS OF SEED SIZE ON SEEDLING VIGOUR IN IDIGBO (<em>TERMINALIA</em> <em>IVORENSIS</em>)

Abstract

The effects of seed size on seedling vigour of Terminalia ivorensis were investigated. Seeds were collected from plantations of the species located at the Forestry Research Institute of Nigeria, Ibadan, Oyo State, Ore Forest Reserve, Ondo State and Awi Forest Reserve in Cross River State of Nigeria. Seed sizes were determined by displacement method and two small and large size classes were recognised and used for the study. Seedlings were raised from the two size classes and grown in a completely randomised design under the green house for nine months. Growth analyses of the seedlings were carried out at two-month intervals for the duration of the experiment. Seed size significantly affected all the growth parameters considered on the seedlings. Seedlings from large seeds showed better growth in height, diameter, leaf production, leaf area and biomass production. Also, seedlings from large seeds had a higher relative growth rate (RGR) than those from small seeds. However, seedlings from small seeds had higher values for net assimilation rate (NAR) than those from large seeds.