Climate change impacts on field crops with reference to stem borer infestation in maize

Climate change is the focus of this research work as a result of the consequences of its impacts on human activities and the natural environment. The survey considered two locations: Abadigba and Apata-Okene, as well as three sowing periods: March/April, April/May and June/July, while 10 farms were sampled /sowing period. Surveys of 60 (30 farms/location) purposely selected farms measuring at least an acre were conducted to ascertain the prevalence of stem borer incidences among sampled maize farms. A total of 240 quadrate throws (75×75cm) were randomly conducted at an average of 4 quadrate throws per maize field and investigated for stem borer infestation then tagged for subsequent data collection. Data were collected by either manual counting of affected plants and recorded as percentage of plants in the sampled quadrates, or by visual assessment as it affects levels of leaf damage resulting from stem borer activities. Data collected include: number of infested maize stands per quadrate throws expressed in percentage; assessment of the levels of leaf damage; and cobs yield per maize stand. Results obtained from the farm surveys were subjected to the percentile method of presentation. The results reveal varying degrees of stem borer infestation and crop damage; percentage infestation varies with planting date, as well as location, with crops sown between March and April suffering the highest infestation, while those sown between June and July gave the least pest infestation in both locations.