Mechanisms regulating bitter pit development in 'Greensleeves' apples with suppression of ethylene biosynthesis

S.T. de Freitas, C.V.T. do Amarante, A.M. Dandekar, E.J. Mitcham
2017 Acta Horticulturae  
The objectives of this study were to understand the role of ethylene and nutrients (Ca 2+ , Mg 2+ , K + and N) on bitter pit (BP) development in wild type (GS) and ethylene suppressed (68G and 103Y) 'Greensleeves' apples. The transgenic line 68G is suppressed for 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) and line 103Y is suppressed for ACC synthase (ACS). Suppression of ethylene biosynthesis reduced BP incidence and severity. Lower ethylene biosynthesis, in ethylene-suppressed
more » ... notypes, had no effect on Ca 2+ , Mg 2+ , K + and N concentrations in fruit cortical tissue. In all genotypes, fruit with BP had lower Ca 2+ and higher Mg 2+ concentrations and higher Mg 2+ /Ca 2+ ratio in cortical tissue. The results indicate that high levels of ethylene biosynthesis and Mg 2+ in cortical tissue can enhance fruit susceptibility to BP incidence.
doi:10.17660/actahortic.2017.1179.10 fatcat:k62tv3iwybbmvjzxe75gxhykxy