COMPOSITIONAL CHANGES IN SPINACH (SPINACI A-OLERACEA L) GROWN IN THE SUMMER AND IN THE FALL

Changes in carotenoid, ascorbic acid, reducing sugar, chlorophyll, nit rate, and soluble and insoluble oxalic acid contents in the leaf blade , petiole, and the edible portion of developing spinach plants were de termined. The summer and fall cultivars studied were 'Magic' and 'Lead ', respectively. In this summary, the chlorophyll content is expressed as mg/100 cm2 of leaf area. The data for the remaining constituents a re for the edible portion based on 100 g fresh wt. 1. Beta-carotene, t he only carotene detectable, for 'Magic' and 'Lead' were 4,450 and 7,3 40 mug, respectively. 2. The total ascorbic acid contents which gradua lly decreased with time in 'Magic' and 'Lead' were 42 and 71 mg, respe ctively. 3. The reducing sugar content in 'Magic' decreased with leaf age, whereas that of 'Lead' increased. At harvest, the reducing sugar content in 'Lead' was 1.12 g ; that of 'Magic' was 0.07 g. 4. Chloroph yll content in 'Magic' remained nearly constant at 3.2 mg, whereas tha t of 'Lead' increased slightly from 3.8 to 4. 1 mg by harvest. A posit ive correlation exists between chlorophyll and 8-carotene contents. 5. Nitrate contents of 'Magic' and 'Lead' were 2,500 and 2,400 ppm, resp ectively. 6. Soluble oxalic acid contents at harvest for 'Magic' and ' Lead' were 740 and 560 mg, respectively. The ratio of the soluble to t otal oxalic acid was 0.871 in 'Magic' and 0.800 in 'Lead'.