Part 2: Selecting for Desired Traits

From plants in the wild to our kitchen! Modern crops were domesticated from wild relatives. Over time, humans have selected those plants that exhibited traits that are in OUR (humans) interests.  Traits that have been selected for by humans include:

  • Larger fruit, more kernels.
  • Determinate growth habit (flowering occurs at the top of the plant, preventing further growth)
  • Retention of mature seed on the plant (loss of grain shattering)
  • Synchronous ripening, shorter maturity
  • Lower content of bitter tasting and harmful compounds
  • Reduced sprouting (higher seed dormancy)
  • Improved harvest index (the proportion of the plant which is used); larger seed or fruit size
  • Elimination of seeds, such as in banana

Figure 3 shows examples of a cultivated corn variety and a wild relative, teosinte.  Note the difference in grain shape and grain number.

Figure 3: Wild type relative of corn ( left) and domesticated corn (right) Image:  John Doebley , University of Wisconsin-Madison, used with permission at http://teosinte.wisc.edu/images.html