Effect of light and carbon dioxide on photosynthesis,chlorophyll fluorescence,and fruit yield in strawberry ( Fragaria × ananassa Duch.) plants

Abstract

BACKGROUND:

The use of two-floor bench bed systems to improve the strawberry productivity in Korea is increasing.

OBJECTIVE:

This study aimed to investigate the effect of different combinations of light intensity and carbon dioxide (CO₂) concentration on photosynthesis, chlorophyll fluorescence, and fruit yield in strawberry (Fragaria × ananassa).

METHODS:

A two-floor bench bed system was used for light intensity treatments. CO₂ fertilizer was supplied, from December 5 to January 30, when the concentration in a greenhouse fell below 700μmolmol^–1, while the control received only ambient CO₂.

RESULTS:

Strawberry plants that were grown under high light intensity in the upper bed had a higher photosynthesis rate than plants grown under low light intensity in the bottom bed; however, light intensity had a negligible effect on the stomatal conductance (Sc) and transpiration rate (Tr) of strawberry leaves. In contrast, CO₂ fertilization lowered Sc and Tr values in strawberry leaves. Plants grown under low light intensity without CO₂ fertilization had the highest chlorophyll fluorescence decrease ratio. Fruit yield was highest in plants grown under high light intensity, with CO₂ fertilization having relatively little effect; however, CO₂ fertilization stimulated the accumulation of anthocyanins.

CONCLUSIONS:

CO₂ fertilization is effective in a two-floor bench bed system.