Life Cycle, Host Range, and Reproduction of Heterodera betulae.

Heterodera betulae, a cyst-forming nematode, originally recovered from roots of river birch in Arkansas, appears to have a limited host range. Of 80 plant species in 20 families tested, only five species of Betula and Cleome spinosa supported reproduction. The minimum time for a complete life cycle was 52 days at 28 C. No reproduction occurred at 31 C or above, and development was very slow below 20 C. Successful population propagations from single larvae demonstrated that males were not necessary for reproduction.