Evaluation and release of East African highland cooking banana ‘Matooke’ hybrids
Authors: Madalla Noel 
Published: February 2023

The production of East African highland bananas Eastern Africa is under threat by pests and pathogens. Improved banana cultivars with high and stable yield, suitable end use quality, host plant resistance to major pests and pathogens, and adaptation to target population of environments can help boost productivity when combined with sound crop husbandry practices. This study evaluated 24 primary and secondary 'Matooke' banana triploid hybrids [NARITA (N)], six triploid local 'Matooke' cultivars, and one exotic cultivar over three years at three highland sites in Uganda's western and central regions, as well as three sites in Tanzania's northeastern and southern highlands regions. The aim of this investigation was to; (1) assess the relative importance of characteristics used by farmers in Uganda and Tanzania to select improved ‘Matooke’ banana cultivars, (2) identify high-yielding banana genotypes with specific and broad adaptation potential, (3) contribute to the release of four ‘Matooke’ hybrids banana cultivars with the potential of adoption by farmers in East Africa, and (4) carry out molecular verification of newly bred cultivars, ensuring the release and supply of true-to-type banana cultivars to farmers. We used farmer participatory approaches to understand farmers' preferences for cultivar characteristics, as well as mixed models (i.e., restricted maximum likelihood/best linear unbiased prediction), and additive main effect multiplicative interaction model biplots to dissect and visualize genotype-by-environment patterns. Large fruit, a large bunch, market acceptability of the banana bunch, a sturdy stem, and an attractive appearance of the banana plant were the characteristics that Tanzanian and Ugandan farmers preferred the most. Farmers of both genders were more focused with production-related characteristics, but men valued marketing-related characteristics more while women preferred use-related characteristics. The highly significant effects of both genotype and interaction of the likelihood ratio test indicated the influence of genotype and site heterogeneity in selecting specific and broadly adapted cultivars. N23 had the highest yield at all sites related to adaptability and stability, outperforming the mean genotype-wide yield by 34.2%. N27 (2nd), N7 (3rd), N18 (4th), N4 (5th), N12 (6th), and N13 (7th) in Tanzania, as well as N17 (2nd), N18 (3rd), N2 (4th), N8 (5th), N13 (6th), N12 (7th), N4 (8th), and N24 (9th) in Uganda, had high yield, stability, and adaptability. Lyamungo in Tanzania and Sendusu in Uganda were the best sites for discriminating breeding clones. As a result, these testing locations are suggested as prime examples of locations to test and choose superior genotypes. Furthermore, Pseudocercospora fijiensis, a fungal pathogen, causing black leaf streak (BLS) did not have a significant effect (P > 0.05) on the hybrids' yield, stability, or adaptability. The four released 'Matooke' hybrids (TARIBANs) have the potential to improve the quality of life of millions of people in the East African region and ensure food security because they combine high yield, farmer desired characteristics (including cooking attributes), and host plant resistance to the BLS pathogen. Over 90% of the 'Matooke' cultivars were be true-to-type, and the microsatellites markers used in this study produced repeatable polymorphic bands in 26 'Matooke' and exotic banana cultivars, thus demonstrating their value as a powerful tool for investigating genetic diversity and establishing relationships among 'Matooke' cultivars. This demonstrates genotyping's ability to precisely identify and validate clones.