Radiation interception and its efficiency for dry matter production in three crop species in the transitional humid zone of Nigeria

Abstract

This study was conducted in two years at the experimental fields of the International Institute of Tropical agriculture, Ibadan (7°30′ N, 3°54′ E) situated in the humid zone of Nigeria. The objective was to determine the biological productivity of cowpea (Vigna unguiculata L.), groundnut (Aranchis hypogea L.) and maize (Zea mays L.) in a transitional humid forest zone of Nigeria. Crop productivity was determined by calculating the Radiation Use Efficiency (RUE) from the slope of the relationship between cumulative dry matter and Intercepted Photosynthetic Active Radiation (IPAR). Linear relationships were observed between cumulative total dry weight and cumulative Photosynthetic Active Radiation (PAR) in all the crops. The mean radiation use efficiencies (RUE) obtained were 3.83 g·MJ-1 for maize, 2.37 g·MJ-1 for groundnut and 2.95 g·MJ-1 for cowpea. The maize crop was a better converter of intercepted PAR to dry matter than groundnut and cowpea.