Abstract
Experiments were conducted to clarify the effects of lower concentrations of streptomycin (SM) application on seedlessness percentage and bunch quality of ‘Fujiminori’ grapes.
1) Application of 100ppm or 200ppm SM before flowering produced approximately 100% seedless berries. 100ppmSM induced lager berries and rachis and lower acidity compared to 200ppm SM (conventional). No deleterious effects were detected in berries treated with 100ppmSM.
2) Application of 100ppmSM with 25ppm gibberellin (GA) at the flowering stage in aim to reduce labor also produced enlarged berries, but lowered seedlessness percentage compared to the single SM application before flowering. Application of 200ppmSM with GA three days before full bloom produced berries that were nearly 100% seedless and of high quality in terms of color, sweetness and acidity.
