Quality and composition of lettuce (cv. 'Plenty') grown in soil and soilless culture.

摘要

Lettuce cv. Plenty plants were grown hydroponically or in the soil in an unheated glasshouse. The plants were transplanted in the soil and into steel troughs filled with perlite or pumice of 0-8 and 5-8 mm grades. The experiment lasted until 81 daysafter transplanting. Plants grown in the soil exhibited excellent visual quality and were free from any defect and tipburn symptoms. In contrast, hydroponically grown plants had some minor defects and developed some tipburn symptoms, especially when grown in perlite. Hydroponically grown plants had lower dry matter, chlorophyll, Mg, Fe, and Mn contents and had higher titratable acidity and nitrate, N, P and contents than those grown in soil culture. No significant differences between plants harvested from the soilless and soil culture were observed for pH, soluble solids and Ca content, and tristimulus values of leaf colour.