GROWING METHODS AND CHEMICAL DRENCHES CONTROL CALLA SOFT ROT

Bacterial soft rot, caused by Erwinia carotovora subsp. carotovora, is the most important disease affecting callas grown in New Zealand.
The aim of this experiment was to determine the effects of chemical drench treatments on the incidence and severity of soft rot in callas grown in soil and in sawdust.
There were four drench treatments: (1) no drench; (2) one drench application immediately after planting; (3) drench applied after planting, then at 28-day intervals; (4) drench after planting, then at 28-day intervals from the first visible occurrence of soft rot plot.
The soil drench was an aqueous solution of 0.05% Kocide^® (350 g/kg copper), 0.05% Terrazole^® (350 g/kg etridiazole), and 0.15% Terrachlor^® (750 g/kg quintozene). Five litres of drench solution per plot was applied to the soil around the base of each plant.
More calla plants died when grown in soil than in sawdust for each drench treatment.
For both growing media, drenching plants at 28-day intervals resulted in the lowest numbers of dead plants during crop growth and rots in lifted tubers.

IX International Symposium on Flower Bulbs

P.J. Wright, G.E. Clark, J. Koolaard

Zantedeschia, Erwinia carotovora, chemical control, agronomic methods

https://doi.org/10.17660/ActaHortic.2005.673.109