Utilization of poor fruit-filling banana progenies to broaden the genetic base for improvement

Enhancing bananas (Musa sp.) through traditional breeding methods is difficult because of the intricate reproductive biology of the plant. This study evaluated the breeding potential of Kothia (ABB)-based progenies, which are typically discarded due to poor fruit filling. Hybridization of Kothia with diverse AA diploid accessions resulted in progenies with low seed set, poor regeneration rates (5.4%), and low frequency of parthenocarpy progenies (0.09%) reflecting inherent cross-compatibility limitations. Among 56 full-sib progenies (FSPs), only one exhibited parthenocarpy, while the rest were non-parthenocarpic with variable female fertility. Two parthenocarpic half-sib progenies (HSPs) were also obtained from these FSPs. Flow cytometry revealed ploidy variation, with most progenies being diploid, and some showing triploid or aneuploid status. Heterosis analysis found that most agronomic traits in FSPs had a negative relative heterosis, but HSPs showed positive heterosis for the number of hands per bunch. Interestingly, six FSPs and both HSPs were resistant to Fusarium wilt (Foc race 1), suggesting they could be useful in breeding programs for disease resistance. One HSP (Pr. 933) displayed a phenotype closely resembling the commercial cultivar Grand Nain (AAA). Another HSP (Pr. 932) showed significantly higher β-carotene content than commercial cultivars and even surpassed some provitamin A-rich plantains. Volatile compound analysis revealed a unique aroma profile in Pr. 932, contributing to its superior flavor. This study shows that using non-parthenocarpic, poor-fruit-filling progenies can help increase the genetic diversity of bananas, allowing for the use of disease resistance, better nutrition, and unique taste qualities.