Morphophysiological and technological assessment of genetic variation of sugar beet ( <i>Beta vulgaris</i> L.) under rhizomania infection

Current research aimed to assess the performance of several sugar beet (Beta vulgaris), hybrids under Rhizomania infection. Comprehensive sets of traits were analyzed, including morphological and growth traits, quality and chemical composition traits as sugar content (SC), sodium (Na), alkalinity coefficient (AC), potassium (K), nitrogen (N), white sugar content (WSC), extraction coefficient of sugar (ECS), and molasses sugar (MS); pathological traits for rhizomania disease as infected plants (IP), infection incidence (II), and infection severity (IS); and yield traits as sugar yield (SY), and white sugar yield (WSY). The results indicated highly variations among genotypes, showing genetic diversity and potential for selection. Factor analysis identified five factors explaining about 89.4% of the variation: (i) biochemical purity-yield efficiency, (ii) vegetative vigor, (iii) disease resistance, (iv) stand stability, and (v) root productivity. In cluster analysis cluster-B contained genotypes that combined high sugar purity and extraction efficiency with moderate yield and Rhizomania tolerance, representing the most desirable group for cultivation and breeding programs. The results emphasized that technological traits like WSC, and ECS, were more critical determinants of white sugar yield than vegetative vigor or root characteristics. Thus, breeding efforts should focus on enhancing biochemical efficiency and Rhizomania resistance rather than increasing biomass production.