Yield Increase as Influenced by Transplanting of Sweet Maize (Zea mays L. saccharata)

Abstract

Aims: Little is known about the response of sweet maize to particular short- and long-term stresses such as the root restriction imposed by small plug cell trays when a transplant routine is used. The aim of this work was to describe the effect of a transplant routine on the physiological components of yield in two sweet maize mutants by means of experiments conducted in a marginal maize production area. Study Design: Two maize mutant hybrids: ‘Canner’ (su1) and ‘Butter Sweet’ (sh2) were sown in plastic plug trays (128 cells tray-1) and transplanted 15 days after emergence or direct seed. Place and Duration of Study: Experiment was conducted at the INTA Balcarce Experimental Station, Argentina (37º45′ S, 58º 18′ W) during the 2009-2010 and repeated twice during 2010-2011 and 2011-2012 growing seasons. Methodology: Plants from direct-seeded or transplant were grown under a field environment. A randomized complete factorial design with three blocks was used. Results: Results showed that transplanted plants showed increased light interception, harvest index, and yield per unit area than direct-seeded ones. These responses were related to a change in leaf area development, crop architecture and anatomical traits such as the phloem/xylem ratio and vascular bundle/mesophyll ratio. Conclusion: A change in leaf area development and crop architecture when using transplanted plants allow increasing sweet maize yield on an area basis. To understand the mechanisms associated to the morphological changes related to transplant and their importance on population architecture would be a key matter for a future breeding program.