Weed composition and maize yield in a former tin-mining area: A case study in Malim Nawar, Malaysia

Abstract

Weed species composition has been assessed for major crops such as rice, rubber, and oil palm but not for cash crops in Malaysia. In this study, we determine the associations between maize yields and weed species, weed density, mean temperature, and mean rainfall. Annual field surveys of weeds were conducted in maize (Zea mays L.) in a former tin-mining land in Malim Nawar, Perak, Malaysia, during June of 2017, 2018, and 2020 to determine the effects of weeds on maize yields. The field surveys in 2017, 2018, and 2020 involved 120 quadrats (0.5 m × 0.5 m) with 40 replicates. Fifteen species were observed, representing 14 genera and 9 families and consisted of 9 broadleaves, 3 grasses, and 1 sedge. Phytosociological characteristics, namely, frequency, relative frequency, density, relative density, abundance, and relative abundance, were used to analyze weed species composition at the study site. The species with the highest mean density and relative abundance were Cyperus sp., followed by Amaranthus viridis, Eleusine indica, Hedyotis corymbosa, and Phyllanthus amarus. These five species accounted for 65% of the total relative abundance. Individual broadleaf, sedge, and grass weed types were compared between paired years using a two-proportion z-test. The variation in number of individuals in each group was significant between 2017 and 2018, 2018 and 2020, and 2017 and 2020. The relationship between maize yield and mean rainfall, mean temperature, and weed species was analyzed using a general linear model, none of which affected maize yields. The results of this study provide a foundation for practical weed management in maize fields in Malaysia, thereby contributing to sustainable agriculture and food security.