March 17, 2009

Corn root structure causes yield increases

An Australian-led study has found corn yield increases during the past 80 years in the U.S. corn belt are mostly due to the crop's changing root structure.

The researchers, led by Professor Graeme Hammer of the University of Queensland, said scientists investigated the importance of the effects of leaves and roots on the dramatic increase in corn yield and found the root structure might be the key to understanding how the crops have grown so efficient.

The team of scientists from Australia and the United States said their approach involved the use of virtual plant computer simulation technologies.

The study revealed the historical corn yield trend and its association with higher plant density was more likely related to change in root system architecture than to change in leaf erectness.

The use of dynamic crop models helped us to look beyond the clearly visible differences among hybrids in this time series of yield advance, said Hammer. It enabled us to focus on the driving processes of crop growth that must be responsible for these effects. It is clear that as we move forward we need to look much harder at root systems and how they capture water.

The study is reported in the January-February issue of the journal Crop Science.