2.3 Rice cultivation
A conventional japonica rice (Oryza sativa L.) cv. Nanjing 9108
was planted in three [CO2] environments: CK, SI and
CI in 2016. Rice seeds harvested in each [CO2]
environment was planted in their respective conditions in the next year.
Seeds from CK were also planted in SI and CI OTCs to study short-term
effect of abrupt increase of [CO2] by 160µmol
mol-1(AI160) and 200 µmol
mol-1 (AI200) in 2019.
In 2019, seeds were sown under ambient air conditions on May 20.
Seedlings were manually transplanted into OTCs at a density of three
seedling per hill on June 20. Rice matured on October 28.
Total N was applied at a rate of 25.0 g N m-2 with
basal dressing (60%), one day before transplanting, and top dressing at
tilling stage (20%) and booting
stage (20%) in 2019. The basal dressing was compound fertilizer (N:
P2O5: K2O = 15%: 15%:
15%) and top dressing was urea. Moisture and other field management
measures were in accordance with local practices.