PLANT TOLERANCE OF SALINITY IN GREENHOUSES - PHYSIOLOGICAL AND PRACTICAL CONSIDERATIONS

M. Zeroni
Salinity causes a reduction in the growth and yield of plants. Morphological and physiological symptoms of salinity are described. High air humidity, attenuated radiation levels and air temperatures may alleviate the effects of salinity on growth and yield. Optimum root temperature may have the same effect. All the above environmental factors may impose their effects through reduction in ETP levels. This may be followed by increased stomatal conductivity to water vapor and CO2 diffusion, resulting in higher photosynthesis rates and better water use efficiency. This hypothesis is discussed critically. The conclusion are that the above environmental factors affect mainly the water status of the plant.

CO2 fertilization increases plant tolerance of salinity. This may be due to elevated net photosynthesis rate and improved carbon balance. The short vs. long term effects of CO2 supplementation are discussed, challenging the above interpretation. Another possible hypothesis, correlating salinity stress and CO2 fertilization with ethylene formation and polyamines levels in the plants, is suggested. It is concluded that the closed greenhouse is a good tool for overcoming salinity injury to plants. A functioning closed and partially controlled system based on the liquid optical filter concept is presented and analyzed.

Zeroni, M. (1988). PLANT TOLERANCE OF SALINITY IN GREENHOUSES - PHYSIOLOGICAL AND PRACTICAL CONSIDERATIONS. Acta Hortic. 229, 55-72
DOI: 10.17660/ActaHortic.1988.229.6
https://doi.org/10.17660/ActaHortic.1988.229.6

Acta Horticulturae