ABSTRACT
The two species of Blitum differ from Chenopodium sensu stricto by their rosette habit in the vegetative state, and by the flowers which have three to five sepals united at their base, and which swell at full fruit maturity to become fleshy, succulent, and bright red. Blitum virgatum is infrequently found on old building sites and by the roadside. B. capitatum retains its rosette habit also in long-day (LD) until about 15 leaves have been formed. Flowering was not only determined by photoperiodism but also by the action of cold temperature. A minimum period of cold caused flowering of B. capitatum without elongation, with some flowers forming at the center of the rosette. The two species of Blitum could flower during short-day (SD) by grafting to flower-induced SD Chenopodium. The SD plants used for the grafting experiments were Chenopodium polyspermum and Chenopodium rubrum. Rosettes of B. capitatum and B. virgatum were induced to flower either by LD or cold temperatures.
