Increased Leaf Area (Source) and Yield of Maize in Short‐season Areas¹

Assimilate supply (source) apparently limits grain yield of maize ( Zea mays L.) grown in short‐season areas. One approach to increasing assimilate supply is to increase leaf area per plant. In this 2‐year study, leaf area of a short‐season, single‐cross, hybrid was manipulated by growing plants to tassel initiation under both a long and a short photoperiod. The plants were then transferred to the field. In both years the plants established under the long photoperiod were larger, having more leaves, bigger mean leaf size, and greater leaf area. The larger plants produced higher ear yields, presumably resulting from the greater assimilate supply associated with the greater plant leaf area. The data support the concept that in short‐season regions the selection of genotypes with greater leaf area should result in increased yields.