A field experiment was conducted to evaluate four fodder beet genotypes under Farm of El-Kharga Research Station of the Agricultural Research Center New Valley Governorate during two successive growing winter seasons of  2013/14 and 2014/15. The experiment was carried out in a randomized complete block design (RCBD) with three replications. The present investigation focused on the growth and yielding properties and diseases development. The obtained results show that the tested genotypes of fodder beat were significantly different for yield characteristics viz. average of leaf length, root length, number of leaves/plant and root diameter and yield components viz. fresh and dry weight of root and leaves/plant and total fresh and dry weight of root and leaves/fed. Genotype Splendid recorded the highest leaf length, number of leaves /plant, root diameter in both seasons and their combined data, respectively. Also, this genotype recorded the best root fresh weight/plant, total fresh weight of roots/fed and dry weight of roots/fed. in both seasons their combined data, respectively. While genotype Jamon recorded the highest root length, fresh weight of leaves/plant, total fresh weight of leaves / fed. and total dry weight of leaves/fed in both seasons  their combined data, respectively. On contrary, Splendid fodder beat genotype recoded the lowest fresh weight of leaves /plant, fresh and dry weight of leaves/fed. While, Jamon recorded the lowest fresh weight of root/plant, fresh and dry weight of roots/fed. The combined analysis of data revealed that the treats leaf length, number of leaves per plant fresh weight of leaves per plant and dry weight of roots per fed were insignificant effect by seasons. While the characters, root length, root diameter, fresh weight of root per plant and fresh weight of roots per fad were significant affected by seasons, whereas the mean values of the second season were more than the first season.On the other hand, the tested genotypes were varied to susceptibility to infection with diseases viz. damping-off, root rot/wilt, powdery mildew and leaf spots under natural infection in field. Both Rigour and Jamon genotypes recorded the highest susceptibility to infection with damping-off disease in both growing seasons, while both genotypes recorded the lowest root rot /wilt severity. Splendid and Rigour genotypes were recorded the highest susceptible to infection with powdery mildew in both growing seasons. Starmon and Splendid genotypes were recorded the highest percentage of infection with leaf spot disease in both growing seasons. We could recommend growing genotype Splendid under New Valley Governorate because recorded the highest results in most parameters and resistance to root rot and wilt diseases.