L-Ascorbic acid-l-11C and its oxidation product, dehydro-L-ascorbic acid, produced labeled oxalic acid in oxalateaccumulating plants such as spinach seedlings (Spinacia oleracea) and the detached leaves of woodsorrel (Oxalis stricta and 0. oregana), shamrock (Oxalis adenopylla), and begonia (Begonia evansiana). In 0. oregana, conversion occurred equally well in the presence or absenice of light. This relationship between L-ascorbic acid metabolisnm and oxalic acid formation must be given careful consideration in attempts to explain oxalic accumulation in plants.Oxalic acid accumulates in certain species of plants such as spinach, woodsorrel, and begonia (6,10,12,23,24,26 Recently, Wagner and Loewus (27) described the conversion of L-ascorbic acid-1-'4C to labeled oxalic acid in detached vegetative apices of the lemon geranium (Pelargonium crispum). This observation has been extended by the present study to oxalateaccumulating plants.
MATERIALS AND METHODSSpinach seedlings (Spinacia oleracea, var. Bloomsdale) were grown under greenhouse conditions in a vermiculite-pearlite mixture. Twelve-day-old seedlings were detached from their roots and placed in vials containing the radioactive solution as described in earlier studies (27)