Water stress leads to small fruit: Just basing irrigation on the evapotranspiration rate is not enough

摘要

For many pear growers, irrigation seems like just a routine chore, but irrigation may be the single most important factor determining the size and quality of the fruit, says Dr. Ken Shackel, pomologist at the University of California, Davis. Trees need water because, in order to make sugar to support the tree and fruit growth, the leaves need to stay open and allow carbon dioxide to enter. Carbon dioxide is needed for photosynthesis, and the problem is that when carbon dioxide enters the leaves, it allows water to diffuse out, Shackel explained during the annual conference of the International Fruit Tree Association in California.