MANAGING TRADITIONAL AND SOILLESS CULTURE SYSTEMS TO PRODUCE CORN SALAD (VALERIANELLA OLITORIA) WITH LOW NITRATE CONTENT AND LASTING POSTHARVEST SHELF-LIFE

Corn salad is traditionally cultivated in soil and commercialized as ready-to-eat produce.
Soilless culture system (SCS) allows clean leaf production, easing and shortening postharvest handling in process industries, and to control growth factors.
A comparison between the traditional culture system (TCS) and a SCS was conducted, with two plant densities (1067 and 2134 plants/m²). TCS was simulated in polystyrene trays filled with local soil and peat (1:1 v/v), overhead irrigation, and weekly fertilization.
Forty-cell trays for SCS, filled with 1:1 perlite and peat, were floated in a nutrient solution.
At harvesting plants were packaged and refrigerated for postharvest shelf-life (8 days) evaluations.
After 40 days, plants from SCS were marketable.
Production was significantly influenced by culture system x plant density interactions.
Greater yield was obtained in SCS, particularly with high plant density (1668 g m^-2). Reduced leaf nitrate content was obtained in both systems, reaching 132 and 333 mg kg^-1 f.w. with TCS and SCS, respectively; these values were below the 2500 mg kg^-1 acceptable threshold.
During shelf-life, leaf weight loss was ca 1% and not affected by cultural techniques.
SCS produced high quality marketable plants in 40 days, with low nitrate content, while TCS required an extended growing period.

VII International Symposium on Protected Cultivation in Mild Winter Climates: Production, Pest Management and Global Competition

E. Fontana, S. Nicola, J. Hoeberechts, D. Saglietti, G. Piovano

lamb¿s lettuce, plant density, tray, nutrient solution, irrigation system

https://doi.org/10.17660/ActaHortic.2004.659.98