Effects of the pear tree canopy on photosynthetically active radiation availability.

The relationships existing between radiant energy and photosynthesis have been extensively investigated on the apple/2/but not on the other fruit trees, pear included. In addition, such information resists generalization, owing to the remarkable differences underlying tree morphology and physiology of the different species; furthermore, some disagreement arises regarding the terminology and the units used to evaluate the amount of radiant energy useful for the photosynthetic process.