Effects of the elevated temperature and carbon dioxide on vine growth and fruit quality of ‘Campbell Early’ grapevines (Vitis labruscana)

Abstract

The effects of elevated temperature and CO 2 concentration on vine growth and characteristics of fruits of three-year-old 'Campbell Early' grapevine were investigated. The treatment groups consisted of a control group (ambient temperature and 390 µL·L -1 CO 2), an elevated temperature group (ambient temperature + 4.0°C and 390 µL·L -1 CO 2), an elevated CO 2 group (ambient temperature and 700 µL·L -1 CO 2), and an elevated CO 2 /temperature group (ambient temperature + 4.0°C and 700 µL·L -1 CO2). The average shoot length was 312.6 cm in the elevated CO 2 /temperature group, which was higher than the other groups; with 206.2 cm in the control group and 255.6 cm and 224.8 cm in the elevated temperature group and elevated CO 2 group respectively. However, the shoot diameter showed a tendency of decreasing in the elevated temperature and elevated CO 2 /temperature groups. The equatorial diameter of berries was increased in the higher carbon dioxide concentration, and the soluble solid content was the highest in the elevated CO 2 group, with 14.6 °Brix among all treatment groups and the lowest in the elevated temperature group (13.9 °Brix). The harvest date was approximately 11 d earlier in the elevated CO 2 /temperature group and 4 to 2 days earlier in the elevated CO 2 group and elevated temperature group, respectively. Regarding the rate of photosynthesis and transpiration during the growth period, higher photosynthetic rates were observed in the elevated CO 2 group and the elevated CO 2 /temperature group during the early stage of growth; however the photosynthetic rate was reduced dramatically in summer, which was contrary to transpiration.