ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Comparing potential predictors of scald susceptibility of apples (Malus domestica Borkh.).

Bramlage, W. J.; Barden, C. L.; Watkins, C. B.;

Acta Horticulturae Year: 1993 Issue: No. 326 Pages: 237-244 Ref: 7 ref.

1993

บทคัดย่อ

Preharvest hours below 10 deg C, starch staining patterns of fruits and OD (optical density) 200 nm absorption of hexane extracts of fruit surfaces were tested as potential harvest-time predictors of scald development in apples after storage. In Massachusetts (Mass.), for weekly harvests of Cortland and Delicious fruits during 3 years all 3 indices correlated strongly with scald. In New Zealand (NZ) none was closely correlated with scald on Delicious or Granny Smith. In experiments to separate the effects of ripening from low temperature, ethephon (250 or 500 p.p.m.) was applied to Cortland trees to induce premature ripening under warm conditions. To produce low light intensity during ripening, Cortland fruits were covered with kraft paper bags. No significant reduction in scald susceptibility occurred when fruits were ripened at warm temperature in the presence of ethephon. Bagging delayed the development of scald resistance associated with increasing hours below 10 deg but did not affect ripen

ing. OD 200 values reflected ripening more than scald susceptibility. Hours below 10 deg was the most reliable indicator in Mass. However, NZ tests suggest that a temperature >10 deg is probably the true physiological base temperature for development of scald resistance.