Ml. Desprezloustau et al., RELATING GERMINATION DYNAMICS OF MELAMPSORA-PINITORQUA TELIOSPORES TOTEMPERATURE AND RAINFALL DURING OVERWINTERING, European journal of forest pathology, 28(5), 1998, pp. 335-347
The influence of overwintering conditions on the dynamics of Melampsor
a pinitorqua teliospore germination in spring was assessed in the Land
es forest (south-western France), over 3 years. January accumulated te
mperature was the variable most strongly linked to the date of optimum
germinability (JDOG), in a negative direction. A linear regression us
ing accumulated degree-days and number of rainy days in January accoun
ted for nearly 70% of overall variation in JDOG. Accumulated temperatu
re from October 1 and January 1 to the date of optimum germinability s
howed lower coefficients of variation than JDOG. The best predictions
of JDOG in an independent data set were obtained by using the accumula
ted temperature from January 1 to the dare of optimum germinability or
a linear regression based on accumulated temperature in January. The
mean square root error of prediction was approximately 5 days. The eco
logical significance of the temperature-dependent model is discussed i
n relation to the synchronization of rust and pine phenologies.