Abstract

Climate change influences crop yield vis-à-vis crop production to a greater extent in countries like Nigeria where agriculture depends largely on natural circumstances. This study assesses the effect of observed climatic variables (rainfall, temperature and relative humidity) on yield of major crops which are divided into two groups, tuber crops (cassava and yam) and fruits (pepper and tomatoes) in Ondo State Nigeria. Crop yield and climatic data were obtained from Ondo State Agricultural Development Project (ADP), Ondo State for a period of nineteen years (1996 - 2014). These data were analyzed using SPSS 16.0 and Microsoft Excel in order to evaluate the effect of climate on the yield on reference crops in Ondo State, Nigeria. Multiple regression, trend analysis, and ANOVA techniques were used to analyze the data. The study showed that the rainfall range for the nineteen years was 1013.08 mm; temperature range was 5.14°C and relative humidity range was 11.55%. Variations in rainfall, temperature and relative humidity were found to have effects on cassava, yam, pepper and tomatoes yield by 20.7, 18.6, 26.8 and 15.5%, respectively. It was then recommended among other things that the extension agents should work with the Nigeria meteorological agency to advice farmers in the State in order to use cropping calendar in accordance with the weather forecast since temperature, rainfall and relative humidity had little effect on cassava, yam, pepper and tomatoes yield in Ondo State.

Key words: Climate, rainfall, temperature, relative humidity, Ondo State.