The Quantitative Effect of Solar Radiation on ‘Redhaven’ Peach Fruit Skin Color

Abstract

‘Redhaven’ peach fruits were exposed to various durations of radiation at the end of stage II of fruit development. Exposure of only 3 days (totals about 6280 J·em −2 ) markedly stimulated anthocyanin development. Color development as a function of solar radiation followed a power curve with nearly maximal level obtained after 8 days of exposure (18,003 J·em −2 ). A similar response was obtained with shade screen (40% and 10% of full sun); the greater the shade the less red color developed. Shading fruit with aluminum foil resulted in softer fruit with a lower level of soluble solids as compared to control fruit. Fruit exposure to solar radiation therefore may have a direct effect on fruit sink activity.