Evolution of early determinate tomato cultivars during the last three decades as a result of research conducted at Warsaw Agricultural University

Earliness is a crucial factor of tomato field production in Poland. A. Mich alska and B. Kubicki (1978) conducted the first investigations on tomato ea rliness at the Department of Plant Genetics and Breeding. The main conclusi ons from these studies indicated that it was possible to obtain varieties e arlier than 'New Yorker' as a result of transgression The two new varieties ('Alfa' and 'Akord F-1') proved to be two weeks earlier than 'New Yorker'. However, earliness was correlated with smaller fruit weight (30-40 g). Ar the next stage of experiment some improvement was achieved both in the size of fruit (45 g for 'Beta' up to 70 g for 'Alka') as well as colour intensi ty and good flavour. With the next few years fruit weight was still increas ed (up to 100 g for 'Maskarena') and a higher level of firmness was obtaine d (mid firm fruits for 'Maskarena' and 'Deita'). At present, the Polish Res earch Centre for Cultivar Testing recommends our varieties 'Betalux', 'Prom yk' and 'Delta' as standards.