Vol. 116 (2003): Proceedings of the Florida State Horticultural Society
Citrus

The role of genomics in citrus improvement

Randall P. Niedz
U.S. Department of Agriculture

Published 2003-12-01

Keywords

  • genetic markers,
  • marker-assisted selection,
  • molecular markers,
  • plant breeding

Abstract

Genomic science is revolutionizing biology and is the result of a convergence of advances in computer science with advances in genetics, molecular biology, and chemistry. To illustrate a typical genomic approach, the basic genomic concept of "association" is explained and illustrated using the widely used genomic "association" application of "marker-assisted selection." In this process, pieces of genetic material "associated" with complex plant traits (cold hardiness, fruit quality, disease and pest resistance, etc.) are used as "associated tags" that can be easily and rapidly identified and tracked in standard breeding programs. This eliminates the need to directly test the plant for the complex trait (i.e., grow plants to maturity to test fruit quality), allowing much earlier selection of the seedlings containing the "genetic tag" associated with the trait. Detection of multiple tags provides selection for essentially all desired traits in very young plants thereby allowing more rapid development of varieties with multiple improvements. This paper will demonstrate how the simplicity of the "association" concept will be harnessed to improve the speed and ease at which important problems relating to insect pests and pathogens, and the management of plant germplasm collections will be addressed.