PRELIMINARY INVESTIGATION OF THE DOUBLE-DIFFUSION TECHNIQUE AS A TOOL IN DETERMINING RELATIONSHIPS AMONG SOME MYXOMYCETES,ORDER PHYSARALES

Double-diffusion technique was used to investigate myxomycete relationships within the order Physarales. Extracts of plasmodia of 22 slime mold isolates were reacted with five antisera produced to Plasmodia of Didymium nigripes, Physarella oblonga, Physarum polycephalum, Physarum gyrosum and Fuligo septica. Two isolates of Fuligo septica tested alike. Four isolates of Physarum pusillum did not test alike, and no valid conclusion of the relationship of this species was possible. These isolates showed strong serological affinity: (1) Physarum gyrosum, Physarella oblonga, two isolates of Fuligo septica, and possibly two isolates of Physarum pusillum, and Physarum tenerum; (2) Physarum polycephalum and Physarum flavicomum; (3) Fuligo septica and many of the species tested; (4) Didymium nigripes and at least one isolate of Didymium iridis. In most cases serologial relationships among species tested did not coincide with current taxonomy based on morphology of fructification.