Evaluation of sugar beet multigerm hybrids for resistance to Rhizomania diseases

Rhizomania is one of the most destructive diseases in sugar beet production areas of all over the world and in Iran. Identification and use of resistant genotypes has the most important role to reduce the risk of rhizomania damage. Production of multigerm seeds resistant to rhizomania in SBSI is due to demand of sugar factories in some area such as Khorasan Jonoubi, Khorasan Razavi and Fars provinces. In present research, 27 genotypes (16 multigerm hybrids and plus 11 genotypes or varieties of foreign and domestic sugar beet) plus three commercial varieties including Aras as foreign resistant, Jaam as domestic resistant and IC as domestic sensitive checks were evaluated in four locations: Shiraz (Zarqan research station), Mashhad (Torogh research station), Khorasan Jonoubi (Islamabad Agricultural Co) and Khorasan Razavi (Jovain Agricultural & Industrials Co) for two years of 2011 and 2012. The experimental design was RCBD with four replications in the naturally infected field to rhizomania. In each plot (three rows of 8 m length), yield and quality characteristics of sugar beet were measured in addition to disease resistance assessment. The results showed in 2011, among foreign variety, F-20660 and among hybrids, SBSI011 and in 2012, among foreign variety, F-20706 and among hybrids, SBSI015 produced the highest root yield and white sugar yield. Highest sugar content produced by F-20706 variety in 2011 and F-20676 variety in 2012. Among hybrids in both years, SBSI015+SHR01-P.12 produced highest sugar content. In general, F-20660 produced the highest root yield and white sugar yield and F-20706 highest sugar content. Among hybrids and domestic varieties, 1590 variety and hybrids of SBSI011 and SBSI015+SHR01-P.12 produced the highest root yield and white sugar yield. Highest sugar content produced by 1590 variety and hybrids of SBSI015 and SBSI015+SHR01-P.12.