Responses of girth of two improved Rubber trees (hevea brasiliensis, muell argo) to tapping date, varieties, and soil locations in Akamkpa, Cross River state,Nigeria

Abstract

This research was carried out in Cross River Estates limited (CREL) Akamkpa Cross River Stare, Nigeria. The research evaluated the responses of girth of two improved rubber trees (Hevea brasiliensis, Muell Argo) to tapping date, varieties, and soil locations in Akamkpa, Cross River State, Nigeria. Generally, the soil locations indicated high acidic situation (pH 4.40-4.69), high sand condition (73.7%-80%) including deficiencies in both micro and macro nutrients. The girths of the evaluated varieties (RRIM600 and PR107) were obviously increasing at a very slow proportion, due to poor soil locations as well as long and unregulated tapping dates, which invariably affected their girths, irrespective of the varieties. Although RRIM600 showed improved girth growth compared with PR107 at all the evaluated soil locations (Dukwe, Akamkpa and Uyanga), both varieties recorded higher cumulative mean girth of 121.6cm (RRIM600) and 119.2cm (PR107) at Akamkpa soil location, proving that Akamkpa soil location had improved fertility status compared with others (Dukwe and Uyanga). The significant influence of Akamkpa soil on the girths of the both varieties indicated that soil locations affect the growth of rubber trees, the variety notwithstanding. The improved girth performance by RRIM600 compared with PR107 at all the locations, suggested that RRIM600 was more adaptive and responsive to the agro-ecosystem than PR107. Improved and sustained girth increments of rubber trees will therefore require appropriate soil remediation practices, such as organic and inorganic fertilizers application. Cultivation of recommended varieties and adoption of proper tapping dates are recommended for vigorous girth development.