Panama disease the Cavendish was then thought to be immune, but was immune only to the strain of the fungus that destroyed the Gros Michel. The version that annihilated the Gros Michel was found in only the Western Hemisphere, but the version found in Malaysian soil was different, and the Cavendish is susceptible to it. It killed and spread faster, inspiring more panic than its earlier counterpart in Panama. The newly discovered strain of "F. oxysporum" was named "tropical race 4 (TR4)". The resulting worldwide collapse in the banana trade is said to have inspired the song "Yes! We Have No Bananas".
Plant disease resistance include the Ring and U-box single subunit, HECT, and CRLs. Plant signaling pathways including immune responses are controlled by several feedback pathways, which often include negative feedback; and they can be regulated by De-ubiquitination enzymes, degradation of transcription factors and the degradation of negative regulators of transcription. Plant breeders emphasize selection and development of disease-resistant plant lines. Plant diseases can also be partially controlled by use of pesticides and by cultivation practices such as crop rotation, tillage, planting density, disease-free seeds and cleaning of equipment, but plant varieties with inherent (genetically determined) disease resistance are generally preferred. Breeding for disease