Modern corn hybrids have long been thought to have more erect leaves and therefore are better able to increase biomass through photosynthesis, especially when plant populations are increased. According to the peer-reviewed journal Crop Science, produced by Crop Science Society of America, there is another reason. Newer hybrids are more effective at extracting water deep in the soil profile.
“There is some evidence suggesting that hybrids with narrow root angle have this capability,” a summary of the study states.
Old-style hybrids have wider roots, while modern hybrids tend to drill down to find moisture.