Flooding has more adverse effects on the stem structure and yield of spring maize (Zea mays L.) than waterlogging in Northeast China

摘要

Lodging is a major element restricting the yield and quality of spring maize (Zea mays L.). A 2-year field experiment was implemented to explore the effects of flooding and waterlogging stress on the vascular bundle structure, mechanical properties of the stem and yield of two spring maize hybrids, Demeiyal (DMY1) and Keyul6 (KY16), in Northeast China. Flooding and waterlogging treatments were conducted for different durations (3, 6, and 9 days for flooding and 5, 10, and 15 days for waterlogging) at the seedling (V3), jointing (V6), and tasseling (VT) stages. The results showed that plant height, ear height, stem diameter, stem length, rind penetration strength and transverse bending strength of the third base internode, cortical thickness, number of vascular bundles and stem bleeding intensity all significantly decreased with increasing duration of flooding or waterlogging. These changes led to a decline in the lodging ability of stems and ultimately caused a reduction in yield in both spring maize hybrids. Both maize varieties were most vulnerable to flooding and waterlogging stress at the V3 stage, followed by the V6 and VT stages, and the longer the flooding or waterlogging duration, the more significant the effects of flooding or waterlogging stress on the stem characteristics and grain yield of both spring maize hybrids.