Enhancing fruit size in apple, peach and blueberry

Summary

Fruit size is a commercially important trait and is determined by the extent of fruit growth. Research in my laboratory aims to understand the mechanisms of regulation of fruit growth in crops such as apple, peach and blueberry. Multiple candidate genes affecting cell production and thereby fruit growth have been identified and are currently being characterized. The effects of production practices on fruit growth and development are being evaluated. This information may be useful in developing cultivars with optimum fruit size and for fine-tuning fruit production practices.

Situation

Larger fruit are more profitable to the growers. Fruit growers often indicate that sizing of the fruit is one of the main horticultural issues associated with fruit production. Various internal (carbohydrate, phytohormone) and external factors (light, temperature) affect fruit growth. Mechanisms mediating the effects of these factors on fruit growth and final size are not well understood.

Response

Our research is aimed at identifying genes that control fruit growth. If genes that control fruit size are identified, breeding and/or horticultural practices can be used to manipulate them, and thereby fruit size can be optimized. Multiple candidate genes that affect organ growth by regulating the division of cells and/or their expansion have been isolated from apple. These genes are differentially active across different types of apples and under conditions that alter fruit growth. Variants in some of these genes have been identified by comparing gene sequences across many genotypes. The spatial and temporal expression patterns and the specific functions of some of these genes are being characterized in detail. The impact of horticultural practices such as timing and intensity of crop load reduction on fruit size are being evaluated in apple as well as peach.

Impact

Knowledge gained from these studies can be used to improve production practices and future breeding efforts. The genes identified and characterized in this research may be targeted for selection thereby leading to the development of cultivars with larger fruit size. These genes have also been found to be responsive to common horticultural practices. Hence in the short term, these genes may be manipulated through such practices to optimize fruit size under field conditions. Increase in our knowledge of the effect of the timing and intensity of crop load reduction on fruit growth can lead to the development of location-specific recommendations for this important production practice. This can lead to enhanced fruit size and overall profitability for fruit growers in Georgia.

State Issue

Agricultural Profitability and Sustainability

Details

• Year: 2016
• Geographic Scope: National
• County: Clarke
• Program Areas:
  • Agriculture & Natural Resources