Cavendish Banana Cultivars Resistant to Fusarium Wilt Acquired through Somaclonal Variation in Taiwan

TLDR: In vitro propagation produces banana clones that arc very diverse and may be an ideal procedure for horticulturists to select banana clones producing fruit with different taste and might be possible for plant pathologists to select clones resistant to other important diseases.

Abstract: In vitro propagation produces banana clones that arc very diverse. For 'Giant Cavendish', in addition to resistance to Fusarium wilt, the tissue culture method also generated clones with increased resistance to strong wind, heavier fruit bunches, and sweeter fruit. Therefore, it may be an ideal procedure for horticulturists to select banana clones producing fruit with different taste and might be possible for plant pathologists to select clones resistant to other important diseases. The possibility of applying this technique to the improvement of other crops remains to be exploited. Although 40,000 'Cavendish' plants grown from suckers did not show any visible difference in morphology, about 3 percent of 'Cavendish' plantlets derived from tissue culture were variants. Relatively little is known about the cause of genetic instability induced by the in vitro vegetative propagation. Rapid multiplication and development of cells resulting from mediation of regulators in the tissue culture medium may increase the chance of variation. The mechanism by which the somaclones of 'Giant Cavendish' are resistant to Fusarium wilt is unknown. Since the parental 'Giant Cavendish' is very susceptible to Fusarium wilt, the appearance of resistant somaclones may result from activation of silent resistant genes. However, the creation of resistance genes through mutation as the origin of the resistant phenotype cannot be ruled out. DNA technology will be useful in deciphering the true nature of wilt resistance in the future.