Virus-like symptoms (due to banana streak virus, cucumber mosaic virus, or both) have been observed in plants of Musa hybrids (TMPx) and local landraces included in multilocational trials in sub-Saharan Africa. Virus-like symptom incidence in these multilocational trials was analyzed using the additive main effect multiplicative interaction (AMMI) model. There were significant differences in virus-like symptom incidence among environments, which was highest in the cool, rainy season (14% to 42%) and lowest in the warm, dry season (<10%). Genotypes showed significantly different responses to virus(es), which depended on the environment. There were no plants of AA and AAA bananas showing virus-like symptoms (0% incidence), whereas ABB cooking bananas and a cooking banana hybrid (ABB × AA) seldom showed virus-like symptoms (<2% incidence). The AAB French plantains appeared to have a similar genotypic response to virus(es) (about 10% virus-like symptom incidence) and were regarded as less susceptible than the False Horn plantain `Agbagba', which showed virus-like symptoms in most of the environments (average 21% incidence). Hence, `Agbagba' should be considered a susceptible indicator host because it has a stable susceptible host response to Musa virus(es). Plantain hybrids (AAB × AA) showed virus-like symptoms; however, there were significant differences in genotypic response to the virus(es) among various hybrids (11% to 60%). Epistasis due to transgressive segregation may control the susceptibility of TMPx germplasm to Musa virus(es). The AMMI1 model revealed that an increase in clonal susceptibility resulted in a more unstable response to the virus. Similarly, phenotypic instability was associated with an increase in clonal resistance. Environments with very low (dry season) or very high (rainy season) incidence of virus-like symptoms had unstable virus expression. Scoring virus symptoms in cool environments with low rainfall and low potential evapotranspiration provided an unbiased assessment of genotypic response to Musa virus(es). The AMMI2 model showed that seasonal rather than locational diversity accounted for most of the interaction patterns. This finding may indicate a low level of strain differentiation in the region.
Ricardo Goenaga, Brian Irish, and Angel Marrero
Dallot, S. Acuña, P. Rivera, C. Ramírez, P. Côte, F. Lockhart, B.E.L. Caruana, M.L. 2001 Evidence that the proliferation stage of micropropagation procedure is determinant in the expression of Banana streak virus integrated into the genome of the FHIA
Randy C. Ploetz, Jody L. Haynes, Aimé Vázquez, and David Benscher
In 1995, 37 new dessert and cooking bananas (Musa spp.) were introduced into South Florida for evaluation under local edaphic and environmental conditions. The number of pseudostems per mat, height at fruiting, and cycling time were determined during the first fruiting cycle, and bunch number and bunch weight were recorded from 1996 to 1998. A productivity index (PIX), calculated as 100 × mean bunch weight in kg/cycling time in days, was used to determine the productivity of the clones over time. Informal taste panels assessed the appearance and organoleptic qualities of fruit on a subjective 1 to 4 scale. In a separate experiment, the susceptibility of 30 of the clones to fusarium wilt, caused by Fusarium oxysporum f. sp. cubense, was assessed. Some of the most popular and productive clones were susceptible to fusarium wilt and are not recommended for production in areas that have a history of this disease. The dessert clones `Pisang Ceylan', FHIA01', FHIA02', and FHIA17' and the cooking accessions `Kandrian', `Kumunamba', and `Saba' resisted fusarium wilt, produced moderate to high yields (PIXs ≥ 1) of good to excellent fruit (mean ratings ≥ 3), and are recommended for use in all areas in Florida.
Brian M. Irish, Ricardo Goenaga, Sirena Montalvo-Katz, Bernardo Chaves-Cordoba, and Inge Van den Bergh
., 2013 ), its disease resistance was high when compared with the other test and reference genotypes. Banana streak virus symptoms had been noticed in other ‘FHIA-21’ plantings at the research station (B. Irish and R. Goenaga, personal observation), and