Effect of cultivar mixtures on the wave velocity of expanding yellow stripe rust foci in winter wheat.

Abstract

The wave velocity of an expanding focus of Puccinia striiformis was studied in 4 mixtures of the susceptible cv. Okapi and the resistant cv. Sarno grown in ratios of 1 : 0, 1 : 1, 1 : 2 and 1 : 4. Two methods of calculating velocity were employed: (a) the gradient method, based on the disease gradient moving away from the focus with time, and (b) the area method, calculated from the enlargement of the diseased area with time. Results revealed a logarithmic relationship between the wave velocity and the proportion of susceptible plants in the mixture. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Effect of temperature on epidemiological parameters of Puccinia lagenophorae

“…Stripe rust on wheat, caused by Puccinia striiformis , spreads with a velocity of 8 cm day −1 (Van den Bosch et al ., 1988c), which is comparable with the spread of Uromyces fabae on broad bean, Uromyces appendiculatus on French bean, and P. recondita on wheat (Zadoks & Van den Bosch, 1994). Buiel et al . (1989), however, reported a velocity of 3 cm day −1 for P. striiformis and explained this low velocity, compared to the findings of Van den Bosch et al .…”

“…(1988a, 1988b). Both models have gone beyond the theoretical/construct stage and are intensively used by ecologists and epidemiologists (Buiel et al. , 1989; Van den Bosch et al ., 1988c; Van den Bosch et al.…”