SEED MATURITY AND DESICCATION AFFECT CARBOHYDRATE-COMPOSITION AND LEACHATE CONDUCTIVITY IN SHRUNKEN-2 SWEET CORN

This study was conducted to determine if changes in the raffinose : su crose ratio in embryos of shrunken-2 sweet corn (Zen mays L.) hybrids were related to differences in seed leachate conductivity between two hybrids harvested at four maturities and artificially dried to 0.10 g H2O/g fresh weight. The ratio of raffinose : sucrose differed for 'Cri sp N' Sweet 710' (CNS) and 'How Sweet It Is' (HSII). The mass ratio of raffinose : sucrose in CNS was >0.3 in seed harvested between 0.44 to 0.64 g H2O/g fresh weight and increased as seed dried from the initia l harvest moisture to 0.10 g H2O/g fresh weight. Raffinose : sucrose r atios of HSII were <0.3 at all harvests between 0.55 to 0.72 g H2O/g f resh weight, but changes during desiccation were not as pronounced. Le achate conductivity of whole seeds of CNS and HSII decreased as seeds were harvested at progressively lower moisture contents. We suggest th at a higher raffinose : sucrose ratio may be indicative of increased s eed vigor in shrunken-2 hybrids.