The estimation of productivity and yield of linseed (Linum usitatissimum L.) using the growth analysis

in three year field experinients (2001-2003) the growth, yield and productivity of 8 flax cultivars were compared. Cultivars 'AC Linora', 'Flanders', 'Linola (TM) 947', 'Norlin' and 'Omeg' were obtained from Canada, 'Barbara' and 'Hungarian Gold' frorn Hungary and 'Opal' frorn Poland. Apart frorn the estimation of the yield of above-round parts dry matter and seed yield the determinations of the primary index value of growth analysis were done and on their basis the indices LAI, LAD, RGR, CGR and HI were calculated. The obtained yield results of the examined flax cultivars show significant genotypic - environmental relationships pertaining to the dynamics of dry matter LICCUMUlation and tile aniount of seed yield. Meteorological conditions in the successive years significantly influenced the particular phases of growth and development of cultivars and the factor which increased the amount of dry matter was the air temperature during the period of plant emergence - budding. During the vegetative season with a large amount of rainfall the average seed yield was about 40% lower than compared with a year of average precipitation and it warm second part of the second period of flax vegetation. Among the analyzed cultivars a stable yield in all the years was characteristic for cultivars 'Flanders', 'Barbara' and 'AC Linora' (that cultivar, however, during a wet year yielded at a low level). The assimilation leaf surface of the linseed quickly increased during the period frorn budding to flowering and the accumulation of dry matter of the aboveground parts lasted up to the green maturity. In the successive years of the experiment there were observed significant (linear or logarithmic regressions) relationship between the yield of dry matter and the indices of growth analysis. The biggest values of the CGR indicator were observed for the period from budding to flowering. The maintaining of a high CGR value after plant flowering in the year with a favourable course of climatic parameters was beneficial for a better yield of all flax cultivars. The low values of the RGR index after flowering of cultivar 'Hungarian Gold' and 'Opal' strictly corresponded to their low yield of seed and straw biomass.