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Potential benefits of biotech application to fruits |
A. DANDEKAR, Dept. of Pomology, Univ. of California, Davis, 1 Shields Ave., Davis, CA 95616-5200 Breeding of fruit trees is a challenging task for geneticists due to their recalcitrance and long generation time. Horticulturists have traditionally relied on chance selection and vegetative propagation to provide the array of different fruit we consume today. In the future the major challenge will be to grow fruit crops on less land with less resource inputs while conserving/enhancing their quality and nutritional characteristics. DNA transformation, a key biotechnology tool, has been used to introduce novel genes as well as to manipulate endogenous genes. Initially, the major emphasis focused on resistance to diseases and pests, traits important to growers. The expression of insecticidal proteins from Bacillus thuringiensis to combat specific insect pests serves as a particularly good example of a technology that is working well in the field to reduce the use of chemical pesticides. More recently, emphasis has shifted towards modifying traits that are more consumer oriented such as enhanced quality and nutritional value. Specific traits under investigation include sugar, flavor, texture, color and ethylene metabolism to improve shelf life and eating quality in fruit. The manipulation of productivity traits like flowering (time and position) and fruit set will influence harvest date. Development of self-compatible fruit cultivars is an example of a major productivity trait to improve fruit set. The manipulation of quality and nutritional value requires a fundamental understanding of the network of genes in fruit that determine these traits. Molecular and computational tools such as DNA sequence analysis, genome mapping, EST database development and expression profiling are becoming integrated and automated increasing greatly the pace of gene discovery and gene manipulation. These technologies will also provide diagnostic tools to streamline production and improve quality control for the marketing of fresh fruit.
Session 34, Biotechnology to improve quality of fruits and vegetables: Potential, safety and consumer acceptability
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