Location: Tropical Crops and Germplasm ResearchTitle: Evaluation of banana hybrids for tolerance to black leaf streak (Mycosphaerella fijiensis Morelet) in Puerto Rico) Author
Submitted to: Crop Protection Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/16/2013
Publication Date: 12/1/2013
Citation: Irish, B.M., Goenaga, R.J., Rios, C., Chavarria-Carvajal, J., Ploetz, R. 2013. Evaluation of banana hybrids for tolerance to black leaf streak (Mycosphaerella fijiensis Morelet) in Puerto Rico. Crop Protection Journal. 54:229-238. Interpretive Summary: Black leaf streak is a destructive disease caused by a fungal plant pathogen of bananas which was recently detected on the island of Puerto Rico. To provide sustainable options to the banana industry, a number of man-made disease resistant banana hybrids were introduced from international breeding programs for field evaluations. Many of the hybrids were disease resistant in the evaluations and several showed superior agronomic traits and organoleptic qualities. Several of the more promising hybrids are being further evaluated in multi-site trials and are being recommended as substitutes for susceptible industry standards and in an emerging organic market.
Technical Abstract: In Puerto Rico, bananas (including plantains) are important agricultural commodities; their combined production totaled 133,500 tons in 2008. Black leaf streak (BLS) and Sigatoka leaf spot diseases, caused by Mycosphaerella fijiensis and M. musicola, respectively, are responsible for significant losses of this crop, due to the high susceptibility of the most important cultivars. Diploid, triploid and tetraploid hybrids were introduced from international breeding programs for evaluation in Isabela, Puerto Rico. Accessions were established in the field in a randomized complete block design and were evaluated over two cropping cycles (2007–2010) for response to BLS and agronomic traits. Significant differences (P <0.05) in BLS severity were observed among accessions throughout both crop cycles and were most pronounced at harvest. When averaged across production cycles, severity indices at harvest ranged from very resistant (20% of the leaf surface affected) for ‘FHIA 02’ to extremely susceptible (97%) for ‘Grand Nain’. Yield attributes varied widely among the accessions, including mean bunch weights (6.9 to 41.0 kg), numbers of hands per bunch (6.6 to 13.4), and the numbers of fruit per bunch (57.0 to 239.2). Several accessions, mainly from the Fundación Hondureña de Investigación Agrícola (FHIA), were BLS resistant and had short pseudostems, large bunches and satisfactory organoleptic profiles. They could potentially replace susceptible cultivars in commercial production or play roles in a nascent organic market.