Banana is an important fruit and food crop, but is threatened by Fusarium wilt, one of the most devastating soil-borne fungal diseases. Only host resistance facilitates banana cultivation in infested soils around the world, but the genetic basis of Fusarium wilt of banana (FWB) is unknown. We selfed a heterozygous wild banana accession Musa acuminata ssp. malaccensis (Mam, AA, 2n = 22) to generate a mapping population and to investigate the inheritance of resistance to Race 1 and tropical race 4 (TR4) that cause FWB. Phenotyping (N = 217) revealed segregation for resistance, and genotyping by sequencing resulted in 2802 high-quality single-nucleotide polymorphic markers (SNPs) that were used for genetic mapping. Combined analyses of these data showed that a single dominant resistance locus controls resistance to Race 1 and maps near the distal part of chromosome 10. Recombinants, together with the position of the putative resistance gene, were further analysed using graphical genotyping, which retrieved markers flanking a 360 kb genetic region that associates with Race 1 resistance. The region contains 165 putative genes on the reference genome, including 19 leucine-rich repeat receptor-like kinase-like genes. At the same position and phase, we also identified a QTL for TR4 resistance, showing that the locus for resistance against Race 1 provided partial resistance to TR4. However, this effect was far less significant and hence not included in the mapping. These data support the breeding of new banana varieties with resistance to Fusarium wilt.

Poerba YS, Ahmad F (2010) Genetic variability among 18 cultivars of cooking bananas and plantains by . This study was done to assess the molecular diversity of 36 accessions (18 cultivars) of the plantain and cooking bananas (Musa acuminata x M. balbisiana, AAB, ABB subgroups) based on Random amplified polymorphic DNA (RAPD) and and Inter Simple Sequence Repeats (ISSR) markers and to determine genetic relationships in the bananas. RAPD and ISSR fingerprinting of these banana varieties was carried out by five primers of RAPDs and two primers of ISSRs. RAPD primers produced 63 amplified fragments varying from 250 to 2500 bp in size. 96.82% of the amplification bands were polymorphic. ISSR primers produced 26 amplified fragments varying from 350 bp to 2000 bp in size. The results showed that 92.86% of the amplification bands were polymorphic. The range of genetic distance of 18 cultivars was from 0.06-0.67.

Musa balbisianaColla, known as Pisang Klutuk/Pisang Batu, is important for banana breeding program due to its B genome and often considered to be resistant to pest, disease and drought. Banana is a big and tall herb up to 7-9 m in height.The study was conducted to assess genetic diversity of 21 accessions of M. balbisiana cultivars/ varieties from Indonesia based on Amplified Fragment Length Polymorphism (AFLP) markers in order to provide basic information to support banana breeding program. Analyses of similarity index of Nei and Li and clustering based on UPGMA was conducted using NTSYS program. Principal Component Analysis (PCA) was conducted by MINITAB 14. Twenty two primer pairs of AFLP markers produced 485 AFLP bands varying from 51-3206 bp in size and 46.18% of the AFLP bands were polymorphic. Genetic diversity among the 21 accessions of M. balbisiana was 13.8%. The genetic diversity of wild M. balbisiana was 12.9%, higher than the genetic diversity of cultivated M. balbisiana which was 11.5%. Cluster analysis based on UPGMA suggested that wild M. balbisiana and cultivated M. balbisiana could not be separated into different clusters. Both cluster analysis and PCA produced the same three groups of the accessions. The PCA analyses showed that 17 AFLP bands were responsible for the grouping.