THE EFFECT OF SUMMER SEEDLING PLANTING DATES ON THE DEVELOPMENT OF SEED STALKS IN SHALLOT (Allium cepa L. var. ascalonicum Backer)

Abstract. Up-to-date production of shallots for commercial purposes was limited due to low supply of the seeding material as well as no breeding cultivars that would produce seeds. Local populations commonly grown in various countries are reproduced mainly in vegetative way, because they usually do not produce generative shoots nor seeds, or they are formed, but in a very reduced number. The aim of this study, conducted in the period 2009–2012, was to evaluate generative growth and seed production in shallot grown from seedlings planted in summer at different dates, without producing mother bulbs. The study included 4 shallot cultivars – ‘Toto’, ‘Ambition F1’, ‘Bonilla F1’, and ‘Matador F`1’. Seed-lings (4 weeks old) were planted in the field on three dates – 3rd decade of July, 1st decade of August, and 3rd decade of August. In the second year of cultivation, after the plants had overwintered in the ground, losses in plants, the percentage of plants producing seed stalks and some traits of these stalks as well as seed yield in the true breeding cultivar ‘Toto ’ were determined. Plants of the other cultivars were not allowed to produce seeds (inflorescence umbels were topped before flower opening), since these were hybrids and undesired cross-breeding could occur. The study showed that overwintering losses in