Influence of Meloidogyne hapla Chitwood, 1949 on Development and Establishment of Heterodera schachtii Schmidt, 1871 on Beta vulgaris L.

Influence of Meloidogyne hapla on estahlishnrent and maturity of Heterodera schachtii in sugarbeet was studied. Results indicated that when the majority of M. hapla were in second, third, or fourth larval stages within plants prior to H. schachtii inoculation, growth and development of the latter was retarded. However, when M. hapla reached the young female stage prior to inoculation of H. schachtii, establishment and development of the latter was greatly enhanced. As M. hapla reached maturity before and after egg production prior to H. schachtii inoculation, establishment and growth of the latter was progressively decreased. In each instance, M. hapla developed independently and matured at the same rate as in plants inoculated with only M. hapla. Usually ratios of total soluble carbohydrates to reducing carbohydrates were lower, but not significantly different, in plants receiving both nematodes as compared to other treatments.