Effects of Temperature and Cyclic Dim Light on the Quality of Cabbage Plug Seedlings during Long-term Storage

Abstract

Cabbage plug seedlings were stored for 9 weeks at 5°C or 10°C under cyclic dim lighting (1.7-7.6 μmol·m⁻²·s⁻¹ of photosynthetic photon flux density with a 1 h-light: 23 h-dark cycle) or darkness. Shoot length and fresh weight of seedlings stored in darkness at 10°C decreased after a transient increase due to etiolation, while those of seedlings subjected to other treatments remained almost constant during the storage period. Dry weights of all seedlings, mainly in the shoots, decreased during the first 5 weeks in storage. The decrease in dry weight was greater in seedlings stored in darkness at 10°C than in seedlings subjected to other treatments. Leaf color of the true leaves was maintained to a higher degree in seedlings stored under light than in seedlings stored in darkness at both 5°C and 10°C. Percent survival after transplantation of seedlings stored at 10°C in darkness decreased with increase in the number of weeks in storage, but percent survival after transplantation of seedlings subjected to other treatments did not decrease throughout the storage period. Head weight at harvest decreased with increase in the number of weeks in storage. Light reduced the head weight loss of seedlings stored at 10°C. These results indicate that cyclic dim lighting is effective for preservation of the quality of cabbage plug seedlings stored for a long period at 10°C.