Evaluating the impact of weather variability on maize yield fluctuation for different sowing dates

Abstract

Frequent and intense adverse weather resulting from climate change can lead to high fluctuations in crop yields. However, sowing dates can be adjusted to avoid adverse weather and thereby mitigate crop yield fluctuation. To elucidate the relationship between the sowing date and fluctuations in maize (Zea mays L.) yield, this study evaluated the effect of weather conditions, including adverse weather, on maize yield during different growth periods. The primary difference in weather conditions between sowing dates was the temperature during the whole growth period and precipitation during specific growth periods; notably, precipitation exhibited higher annual fluctuations. Furthermore, a low relative yield (<70 %) and high coefficient of variation (>15 %) were noted for sowing dates with high annual fluctuation in precipitation and adverse precipitation events frequency. In simulations, the lowest yield and yield stability were those for the sowing dates with high temperature during the crop season and high annual fluctuation in adverse precipitation events frequency during the vegetative stage. In both crop seasons, adverse weather significantly affected maize yield and explained >50 % of observed yield variation. Under the weather scenario of adverse high temperature and precipitation, an approximate 2500-kg/ha reduction in yield was predicted. This study first evaluated the effect of sowing dates on the variation of weather conditions, then correlated these variations to yield fluctuation to identify factors contributing to maize yield fluctuation. The results indicate that adverse precipitation during the vegetative stage affects crop yield fluctuation and sowing dates must be reevaluated under climate change.