Corn in the Bible - a Christian perspective
A single corn can do nothing on its own, but by "dying" and being reborn as a new plant, it can bring forth much new life. This can be seen as a metaphor both for Christ--who would sacrifice himself to bring spiritual life to many--or to the Christian life in general.
http://biblegateway.com/passage/?search=John%2012:24&version=KJV