|Lopez-Sese, Ana Isabel - UW DEPT OF HORT MADISON|
Submitted to: Cucurbit Genetics Cooperative Report
Publication Type: Research Notes
Publication Acceptance Date: December 15, 2001
Publication Date: N/A
Interpretive Summary: The genetic diversity (i.e., genetic differences) of melon market classes (e.g., Western Shipping and Eastern Market type cantaloupes) has be characterized using molecular markers. Molecular marker analysis is a tool that has been derived from the modern biotechnological revolution. Molecular markers are made from DNA (a substance that resides in every cell that is the basis of life) that is used as place markers on the chromosome (single units of DNA that contain genes) to marker the location of genes (the points on the chromosome that provide differences between individuals). Molecular markers were used in this study to study differences between individual melon market class melons in different countries and compare them with U.S. market types. It was determined that great differences exist at the DNA level among melons of different countries. This information allows the melon breeder to choose individual melons for cross-pollination more effectively. This increase in effectiveness will eventually lead to the development of melons with different genetic constitutions (DNA differences). These differences are important because they allow for the commercial use of a variety of melons with different characteristics (e.g., shape, color, etc.).
Technical Abstract: The genetic diversity of melon groups has been characterized using molecular analyses. Random amplified polymorphic DNA markers have been used to assess the genetic diversity of elite germplasm. Likewise, researchers have used the same markers employed in previous studies to define the diversity among African and Japanese germplasm, respectively. We summarized herein the percentage of RAPD band presence within distinctly different geographic regions. Germplasm examined from Europe, USA, and Japan should be considered elite since it presents either refined inbred lines or commercial hybrids. African landrace accessions show genetic affinities to Asiatic germplasm as determined by RAPD marker analysis. The majority of RAPD bands produced by any one primer were in a similar percentage in European and U.S. accessions. Some primers provided products at relatively low frequency in African germplasm that were evident in elite germplasm. Also a lower percent frequency of band presence was observed in Japanese germplasm when compared to European, U.S., and African groups. This work provides genetic information to germplasm curators that will allow them to increase their managerial effectiveness and efficiency. It provides a framework in which more effective choices can be made for use of certain RAPD primers for germplasm analysis.