A team of Spanish researchers has obtained themelon genome, one of the species of greatest economic interest in the world. It is the first time that a Spanish public-private initiative has obtained a complete genome of a superior species of plants (they have flowers and produce seeds) and, furthermore, they have done so usingnew mass sequencing technologies, which are cheaper and more efficient. Together with the complete melon genome, the researchers have been able to sequence, from it, the genomes of seven different varieties. The study is published in the journalProceedings of the National Academy of Sciences (PNAS). The Melonomics project, launched by the Genoma España foundation, has had the participation of nine research centers and the support of five companies.
The results show that the melon has a genome made up of about 450 million base pairs and 27,427 genes, much larger than its closest relative, the cucumber, with 360 million base pairs. “The difference in size is largely due to the amplification of transponible elements and recent duplications of the genome, very frequent in plant species, are not observed”, highlights Pere Puigdomènech, from the Higher Council for Scientific Research (CSIC), co-author of the work.
Another aspect of interest for the study is related to the ripening of the fruit, a process in which characteristics such as taste and aroma are defined. Researchers have identified up to 89 genes related to some of these processes: 26 related to the accumulation of carotenes (which gives the melon pulp its color) and 63 to the accumulation of sugar and, therefore, the flavor of the melon , of which 21 were not previously described. “Knowledge of the genome and genes related to characteristics of agronomic interest will allow progress in the genetic improvement of this species to produce varieties that are more resistant to pests and with better organoleptic quality”, says the IRTA researcher, Jordi Garcia Mas.
The melon is part of thecucurbit family, which also includes species such as cucumber, watermelon, pumpkin and zucchini. Cucurbits have small genomes. “The melon is a species of great economic interest, especially in Mediterranean countries, Asia and Africa. The diseases that affect it, such as the cucumber mosaic virus or fungi, can cause significant economic losses. Therefore, it is expected that genome sequencing has a great economic impact on improving this crop “, details the CSIC researcher.
According to the Food and Agriculture Organization of the United Nations, melon production worldwide is 26 million tons per year. Spain, the fifth largest producer in the world, exports a third of its annual production, which makes it the world’s leading exporter.
