Increasing maize resistance to lodging and frost
Nitrogen supply has to be balanced to ensure good plant growth without increasing lodging risks and delaying maturity. Nitrogen overuse or too much late-applied nitrogen can lead to excessive late growth, resulting in crops with weaker stems that are more liable to lodging. Best practice is to adjust rates based upon local N-responses to local growing practices, taking into account nitrogen available from previous crop residues and/or manures.
Potassium helps minimize the frost damages by acclimatizing the cells to intracellular frost formation, which reduces maize cell rupture. Modern hybrid varieties are relatively cold tolerant. However, while frosts will damage young plants, because the growing point is still below the soil surface until crops reach the V5 stage (about 25-30cm in height), plant loss is uncommon. Removal or death of leaf tissue above the growing point has only a small effect on growth and yield at these early stages.
If a significant frost event occurs before grain maize fill is complete, maize yield and quality could be affected. A less intensive frost could kill leaves but not the stalk or ear shank. When only a portion of the leaves are killed, those not killed can continue to function and contribute to grain yield if good growing conditions follow.