Resistance to brown rot disease in peach is determined by multiple structural and biochemical components
Thomas M. Gradziel, Richard M. Bostock and James E. Adaskaveg
ISHS Acta Horticulturae 622: 2003. pp. 347-352.
2003
บทคัดย่อ
A multi-year evaluation of USDA and UC peach (Prunus persica) germplasm for resistance to fruit brown rot as caused by Monilinia fructicola has identified the Brazilian cultivar ‘Bolinha’ as well as several peach breeding lines derived from almond (Prunus dulcis) as the most promising sources for the transfer of disease resistance ot processign peach. Fruit flesh or mesocarp resistance was often associated with elevated levels of the phenolic compounds chlorogenic and caffeic acids. Elevated levels of these phenolics were also associated with greater susceptibility to fruit bruising making them undesirable for cultivar development. Usable and heritable levels of epidermis-based resistance were recovered following a series of controlled backcrosses. The epidermis of resistant progeny typically possessed thicker cuticles and greater amounts of epicutilar waxes, and higher levels of pectin, phenolics, chlorophyll, and other biochemical compounds associated with immature tissue. Structural components, particularly cuticular and epicuticular waxes were significantly influenced by growing season environment. The concurrent selection for epidermis-based resistance combined with a high (CIEL*a*b*) ‘a’ color value has been successful in breeding resistant genotypes possessing good horticultural and processing quality.