Sweet pepper acclimation to variable CO₂ supply in a Mediterranean greenhouse

Air CO₂ enrichment improves the yield of greenhouse horticultural crops.
The agricultural interest of this technique in Mediterranean climates was confirmed when CO₂ supply was variable, maintaining high concentration when vents were closed and near the atmospheric level when vents were opened.
In the long term, high CO₂ ambient levels cause a reduction in photosynthetic capacity known as acclimation.
This process reduces the efficiency of this technique.
The supply of a fraction of NH₄⁺ as nitrogen source in the nutrient solution can play an important role in maintaining the photosynthetic activity and could be interesting to delay the onset of this process.
The aim of this study was to test whether acclimation occurred in sweet pepper plants when variable CO₂ enrichment was applied in a Mediterranean greenhouse.
The results showed a loss of the photosynthetic stimulation in plants at high CO₂ concentrations after several weeks growing under this strategy.
This acclimation process could be the cause of the reduction in the yield increase rate which was delayed with the ammonium supply.

International Symposium on New Technologies and Management for Greenhouses – GreenSys2015

M.E. Porras, E. Medrano, P. Lorenzo, M.J. Sánchez-González, E.J. Baeza, M.C. Sánchez-Guerrero

Capsicum annuum L., CO₂ enrichment, photosynthesis, NH₄⁺

https://doi.org/10.17660/ActaHortic.2017.1170.102