juin 28, 2009
WASHINGTON, juin 28 (Xinhua) — Plant breeders now have a better chance to develop new melon varieties because melon genome with hundreds of DNA markers has been mapped by researchers from Texas A&M University.
The results are reported in the latest issue of Journal of the American Society of Horticultural Sciences.
"This will help us anchor down some of the desirable genes to develop better melon varieties," said Kevin Crosby, one of the lead researchers. "We can identify specific genes for higher sugar content, disease resistance and even drought tolerance."
Researchers from France and Spain before had completed partial maps of segments of the melon DNA sequence. Maintenant, the Texas researchers connected those segments with new findings in their study to complete the entire melon genome map.
For the study, a special variety of ananas melon was crossed with a wild melon. Plus que 100 of the offspring from that cross were grown in greenhouses. DNA was extracted from leaf tissue collected 21 days after planting. Results from these tests were integrated into partial maps created by other researchers.
In addition to the complete map, the Texas researchers located genetic markers linked to fruit sugars, ascorbic acid (vitamin C) and male sterility, which is useful for developing hybrid varieties.
They said the genetic map will be helpful for future studies in identifying fruit sweetness, quality, size, shape and resistance to disease.
Melons are grown worldwide in a multitude of varieties. Not only are they economically important, the researchers noted, but they are a favorite among consumers internationally.
Éditeur: Zhang Xiang