Yield and nutritive value of selected endive cultivars grown for spring and autumn harvest

A field experiment was carried out in the years 2007-2009 at the Research Development Station of the Department of Horticulture at the Wrocław University of Environmental and Life Sciences. The experiment involved two botanical varieties of endive: var. latifolium (nine cultivars) and var. crispum (five cultivars). Endive was cultivated from transplants produced in a greenhouse in two terms, for spring and autumn harvesting. The harvest took place 90-100 days after the seeds were sown. In the course of harvesting, the total and marketable yields were determined, while biological value was assessed on the basis of analyses regarding the content of dry matter, vitamin C, chlorophyll and carotenoids, as well as the amounts of such elements as Mg, P, K, Ca and nitrates.