Abstract
The transgenic everbearing strawberry (Fragaria×ananassa Duch. ‘HS 138’) can be cultivated in a closed plant production system to produce functional proteins that enhance human immune functions. In this study, we investigated the effects of light quality on fruit growth and the concentration of human adiponectin (hAdi) at three mature stages in transgenic strawberry. hAdi plants were exposed to 3 different light qualities (white [W], blue [B], and red [R]) for a 16-h light period under fluorescent lamps during the flowering and harvest stage; fruits were then harvested at three different mature stages (small green, turning white, and mature red). hAdi concentration increased with fruit maturation, and the mature red stage fruit from the R light treatment group had a significantly greater concentration of hAdi on a fresh-weight basis than all other treatments. There was no relationship between hAdi concentration and fruit fresh weight and the number of days from anthesis to harvest. Although the factors that promoted the production of the functional hAdi proteins were not clear in this study, the results suggest that the fruit growth stages of the transgenic strawberry differed in their response to light quality. For hAdi plants, exposure to red light resulted in the greatest level of functional protein production under the tested treatments.
