Molecular Characterization of Banana (AA) Diploids with Contrasting Levels of Black and Yellow Sigatoka Resistance

Most banana cultivars are susceptible to many diseases, whereas Sigatoka leads to greatest yield losses. One of the strategies to overcome this disease is thorough banana genetic breeding which consists in the obtainment of improved (AA) diploids which are then crossed with triploids obtaining (AAAB) tetraploid disease resistant bananas also presenting other important agronomic characteristics. The prior knowledge of the genetic diversity of (AA) diploids, is therefore considered indispensable in order to direct the crosses being made. The objective of the present work was to analyze the genetic diversity of 20 (AA) banana diploids with contrasting levels of reaction to yellow and black Sigatoka caused by Mycosphaerella musicola and M. fijensis, respectively, using molecular markers. From the dendrogram data it is shown that a great number of experimental hybrids can be obtained from the combination of genetically different diploids, therefore making the banana genetic breeding program more efficient regarding its objectives.