Panama disease in stress-tolerance, yield, or other beneficial traits necessary for commercial varieties. Nevertheless, these efforts are leading to the best control measure for Panama disease of banana. Recently, an R gene (RGA2) was transformed into Cavendish bananas which confers disease resistance to Fusarium wilt tropical race 4. This is the first case of successful resistance in the field and is a promising step towards preventing the loss of the Cavendish cultivars that are a huge portion of banana export production and subsistence of many communities. One major impediment to breeding bananas is polyploidy; Gros Michel and Cavendish bananas are triploid and
Little cherry disease the fruit crop less hidden by the canopy, and leaf symptoms, varying from a slight marginal up-curl of the leaves to marked reddening of leaf surfaces. The general vigor of infected trees may be impaired, though this is not always apparent. Diagnosis of the disease can be assisted by RT-PCR assays. Other "Prunus" species may act as symptomless or tolerant carriers of the disease; especially cultivars of Japanese flowering cherry ("Prunus serrulata") have been implicated as such. There is no known cure for little cherry disease and tolerance breeding programs have not yielded any cultivars able to withstand the effects