Growth Analysis of Sugar Beet in Healthy and Rhizomania Infected Conditions

Viral disease of Rhizomania is one the most important diseases of worldwide sugar beet farms. The disease significantly reduces the yield and quality of sugar beet and imposes high economic loss to farmers. Long-term breeding programs to introduce tolerant varieties are the only chance to avoid further yield losses. This study tried to analyze the growth of shoot and root of rhizomania tolerant and susceptible sugar beet to provide information for improve and acceleration sugar beet breeding programs. Growth indices were used for growth analyzing, quantification, and time course of sugar beet on infested and non-infested soils. A two-year experiment was conducted with four sugar beet varieties in 2010 and 2011. The results of this study showed that under infested soils, root dry matter and leaf area index of the susceptible varieties in comparison to tolerant varieties were lower by 57 and 24 percent respectively. In addition, crop growth rate and net assimilation rate of susceptible varieties were affected by rhizomania and were lower than that of tolerant varieties. On non-infested soil difference between dry matter and growth indices of susceptible and tolerant sugar beet varieties were not significant. Rhizomania decreased of green area and photosynthesis capacity and led to lower growth rate and dry matter production.