Link to home

Temperature Effects on the Disease Reactions of Sunflower to Infection by Orobanche cumana

May 2001 , Volume 85 , Number  5
Pages  553 - 556

S. Sukno and J. M. Fernández-Martínez , Departamento de Mejora y Agronomía, Instituto de Agricultura Sostenible ; and J. M. Melero-Vara , Departamento de Protección de Cultivos, Instituto de Agricultura Sostenible, CSIC, Apdo. 4084, 14080, Córdoba, Spain

Go to article:
Accepted for publication 7 February 2001.

Three virulent populations (CU194, SE193, and SE194) of the parasitic plant Orobanche cu-mana were inoculated onto four lines (KA-41, J-8281, HA-89, and RHA-273) of sunflower (Helianthus annuus L.). Pots were transferred to growth chambers set at 15, 19, 23, and 27°C. Emergence of broomrape plants and infection incidence were determinants of disease reaction. All broomrape populations were pathogenic to the sunflower lines KA-41, HA-89, and RHA-273, although differences in virulence were found. At 15 to 23°C, the populations of broomrape infected these three sunflower lines, but a delay in emergence of broomrape was found at 15°C; whereas, at 27°C, the level of infection was restricted. Only population CU194 infected the resistant line J-8281, with infection occurring mainly at 23 and 27°C, but few broomrape plants emerged. Our results suggest that the effect of temperature on the host-parasite relationship is complex.

Additional keywords: differential lines, resistance genes

© 2001 The American Phytopathological Society