Effect of growth temperature levels on photosynthetic ability and fruit quality of ‘KUPP2’, a new lowchill peach cultivar

Abstract

Temperature is a crucial factor in growing plants in a forcing system. Our goal was to introduce lowchill peach cultivars into a forcing culture for earlyseason peach production with high fruit quality. However, the effects of growth temperature on plant growth and fruit quality during fruit development of the ‘KUPP2’ peach cultivar have not yet been evaluated. ‘KUPP2’ trees were grown in containers and transferred to phytotrons after fruit set in April 2019. The air temperature was set at 20, 25, and 30°C until harvest. Photosynthetic ability, leaf characteristics, and fruit quality under each treatment were determined. Long exposure to lower growth temperatures did not cause a change in leaf characteristics or a reduction in photosynthetic ability and fruit quality in the ‘KUPP2’ peach cultivar. In contrast, the 30°C was found to be associated with a decrease in leaf size and thickness, stomatal density, photosynthesis, chlorophyll content, and fruit size. Conversely, the hightemperature condition enhanced coloration of the fruit peel and hastened the harvesting period, compared with the lowertemperature treatments. These results indicated that longterm exposure to the moderately high temperature of 30°C negatively affected plant growth and fruit productivity through changed leaf characteristics and a disrupted photosynthesis.