FRUIT GROWTH AND DEVELOPMENT AS IT RELATES TO CROP LOAD, THINNING AND CLIMATE CHANGE
Peach fruit growth and development is classically described as following a double sigmoid pattern of increasing fruit mass. But just describing the pattern of fruit mass increase does not provide a functional approach to analyzing factors that limit fruit growth. The key to understanding these limitations is to be able to compare fruit growth that occurs under specified limiting conditions with the potential growth that would have occurred without the limitation. Two decades ago my colleagues and I demonstrated that fruit relative growth rate analysis could be used to provide an approximate description of the genetic fruit growth potential of a given cultivar when that cultivar was grown under near optimal conditions with very low fruit loads. Subsequently we have demonstrated how relative fruit growth rate analysis can be used to develop mathematical models that simulate fruit growth for any given time interval during a growing season. These analyses and models have provided a means to understand the basis of the classical double-sigmoid growth curve, calculate carbohydrate requirements of fruits during growth; evaluate the effects of nitrogen deficiency on fruit growth and yield; analyze time of thinning; amount of thinning and fruit distribution effects on fruit size and crop yield; and study spring temperature effects on fruit size and crop yield. The goal of this paper is to summarize this research and show how the understanding resulting from these analyses and models has been used to provide growers with decision support information that helps them refine their practical crop management operations in the field.
DeJong, T.M. (2012). FRUIT GROWTH AND DEVELOPMENT AS IT RELATES TO CROP LOAD, THINNING AND CLIMATE CHANGE . Acta Hortic. 962, 233-238
double sigmoid growth, relative growth rate, fruit size, fruit sink strength