Abstract
When examining plants of white mustard (Sinapis alba L.), a significant relationship between the size of the roots and the yield was found, both in a pot experiment and in a field one. The yield was influenced by the size of the root system during and after flowering time. Especially the number of seeds has increased, and the average weight of seeds showed the same tendencies after the flowering time. The productivity of plants with an above-average yield was increasing more quickly than the size of their root system. From the beginning of the vegetation till the end of flowering these most efficient plants showed the lowest permitivity dispersion and the highest dispersion after the flowering time. The dispersion has increased towards the end of vegetation. U rostlin horcioe(Sinapis alba L.) pěstovanych jednak v korenácich, jednak ve volné půdě, byla stanovena prokazatelná závislost mezi velikosti kofenového systému a vynosem. Velikost kofene ovlivnovala vynos během doby kveteni a později. Vzrostl zejména pocet zrn a jejich průměrná váha. Produktivita rostlin s nadprůměrnym vynosem stoupala ryehleji nez velikost korenového systému. Od pocátku vegetace az do ukonceni doby kveteni tyto nejvynosnějM rostliny vykazovaly nejnizsi disperzi permitivity a po ukonceni doby kveteni nejvyssi. Disperze se ke konci vegetaeni doby zvysovala.