The effect of growing media on yield and nitrate concentration in lettuce (Lactuca sativa var. capitata L.).

摘要

The effects of growing media with varying nutrient content on the yield and nitrate accumulation of butterhead lettuce (L. sativa var. capitata cv. Mildred), grown during autumn and spring, were investigated. Lettuces cultivated in spring had biggerheads than those cultivated in autumn. During the spring season, the lowest nitrate accumulation was observed in lettuce cultivated on rockwool and in pots on the polypropylene (PP) watering mat. In the autumn season, the lowest nitrate accumulation wasrecorded for plants cultivated on PP mat. Nitrate accumulation was 50% lower in plants cultivated in autumn. On rockwool, N, P, K and Ca accumulation was more than 90% of the total amount of supplied fertilizers when plants were cultivated in spring; however, Ca uptake decreased during autumn.