THE EFFECT OF ROOT ZONE TEMPERATURE ON THE CONTROL OF PHYTOPHTHORA CRYPTOGEA IN ROCKWOOL-GROWN TOMATO PLANTS

R. Kennedy, G.F. Pegg
The effect of root zone temperature on root rot symptom development was studied in tomato cvs Counter and Calypso grown in rockwool culture. November-sown plants which had developed nine trusses were inoculated with a zoospore suspension of Phytophthora cryptogea. After three days incubation at ambient temperature continuous block and slab temperature of 15°C and 25°C were imposed. Both cultivars maintained at 15°C developed acute aerial symptoms and subsequently died. Plants at the higher temperature remained symptomless for the three month duration of the experiment.

Root growth rate was enhanced by the higher root zone temperature with most biomass confined to the growing block. Zoospore levels and root infection were measured throughout the experiment. Higher temperature increased mycelial growth but decreased sporulation. The results are discussed in relation to the effects of temperature on host carbon availability affecting root establishment, pathogen inoculum levels and ecology.

Kennedy, R. and Pegg, G.F. (1989). THE EFFECT OF ROOT ZONE TEMPERATURE ON THE CONTROL OF PHYTOPHTHORA CRYPTOGEA IN ROCKWOOL-GROWN TOMATO PLANTS. Acta Hortic. 238, 165-172
DOI: 10.17660/ActaHortic.1989.238.19
https://doi.org/10.17660/ActaHortic.1989.238.19

Acta Horticulturae