Effects of crop density on root yield and quality of sugar beet cultivars grown on the soil infested and uninfested by rhizomania

Abstract

During a two-year period (1996-1997) we conducted studies on the effects of crop density on root yield and quality of sugar beet cultivars, susceptible and tolerant to rhizomania, grown on the soil infested and uninfested by this pathogen. The results obtained are of importance for both agricultural science and practice. The highest difference in sugar beet studied characteristics was achieved between infested and uninfested soil, between tolerant and susceptible cultivars, and the lowest between crop densities. On the soil infested by rhizomania, on average, root yield was lower by 22.84 t/ha, sugar content by 2.49%, crystal sugar yield by 4.64 t/ha per cultivar and crop density. Tolerant cultivar KWS rama produced higher root and sugar yields on both infested and uninfested soil. However, susceptible cultivars Al omona and Delta, grown on uninfested soil, had higher sugar content in sugar beet root by 0.53%. Increased crop density resulted in higher root and sugar yields, however, considerably higher in the tolerant cultivar and on soil infested by rhizomania.

U dvogodišnjem periodu (1996-1997) vršena su istraživanja uticaja gustine useva na prinos i kvalitet korena sorata šećerne repe, osetljivih i tolerantnih na rizomaniju, gajenih na zemljištu zaraženom i nezaraženom rizomanijom. Ogledi su izvedeni u Sremskoj Mitrovici na zemljištu tipa karbonatni černozem. U ovim istraživanjima su proučavana tri faktora i to: (A) sorta (Al omona i Delta - osetljive na rizomaniju i KWS rama tolerantna na ovu bolest); (B) zemljište (zaraženo i nezaraženo rizomanijom) i (C) gustina useva (60, 80 i 100 hiljada biljaka po hektaru). U istraživanjima su postignuti sledeći važniji rezultati: Najveći uticaj na prinos korena, sadržaj šećera i prinos kristalnog šećera ispoljilo je zemljište, odnosno prisustvo u njemu patogena rizomanije. Na ovakvom zemljištu prinos korena, osetljivih sorata (Al omona i Delta), bio je manji za 30,94 t/ha; sadržaj šećera u korenu za 3,31% a prinos kristalnog šećera za 6,07 t/ha. Tolerantna sorta KWS rama postigla je veći prinos korena i šećera kako na zaraženom tako i nezaraženom zemljištu. Međutim, osetljive sorte Al omona i Delta imale su za 0.53% veći sadržaj šećera u korenu repe gajene na nezaraženom zemljištu. Sa povećanjem gustine useva povećan je prinos i korena i šećera, ali znatno vise kod tolerantne sorte kao i na zemljištu zaraženom rizomanijom.