Damage by Limicolaria species on maize, environmental factors influencing their population dynamics and potential strategies for their management in Cameroon

Abstract

Maize (Zea mays L.) is an important versatile food and industrial crop in Cameroon, Africa and the world. It is a crucial human food source, animal fodder and feed, and raw material for industries but its production is constrained by many pests including Limicolaria species which are currently serious economically important perennial pests of the crop. The extensive losses caused by this pest during the various growth stages of maize are a serious threat to maize production and food security. Therefore, the aim of this study was to investigate the Limicolaria snail pest damage, species composition and abundance, population dynamics, the influencing environmental factors and their implications in managing the pest in maize fields. The Limicolaria snail species were trapped monthly using baited pitfall and litter traps monitored once every week throughout 2020 and 2021 in maize experimental plots planted at a rate of three per hole at 75 x 50 cm inter and intra-row spacing at 5 cm depth respectively. These polyphagous snails damage mostly the maize leaves, stems, ears, fruits (kernel) and dead plant parts of the crop from the seedling to the mature stage. They damage maize by chewing irregular longitudinal or horizontal, translucent/window-like holes on the leaves. Four Limicolaria species were identified namely: L. zebra which contributed to 47% of the total number of snails followed by L. flammea 21%, L. numidica 20%, and L. aurora 12%. Temperature was negatively correlated with the number of Limicolaria caught in 2020 (r = -0.7133) and 2021 (r = -0.885). On the other hand, rainfall and relative humidity were positively correlated in 2020 (r = 0.829 and 0.540) and 2021 (r = 0.684 and 0.759), respectively. Overall, these results highlighted the potential of using baited pitfall and litter traps to monitor/suppress Limicolaria species populations in maize fields while the weather factors could be used to predict the periods of high and low pest populations for proper management through cultural control.