Influence of temperature on decay, mycelium development and sporodochia production caused by Monilinia fructicola and M. laxa on stone fruits

Abstract

Brown rot on peaches and nectarines caused by Monilinia spp. results in significant economic losses in Europe. Experiments were conducted to study the effects of temperature (0-33 °C) on the temporal dynamics of decay and mycelium development and the subsequent sporulation on peaches and nectarine fruit infected by M. laxa and M. fructicola. The rates of decay and mycelium development increased with temperature from 0 °C to 25 °C for both Monilinia species. At 0 °C, decay was faster for M. laxa (0.20 cm days) than for M. fructicola (0.07 cm days); indeed, M. laxa was able to develop mycelia and sporodochia, but M. fructicola was not. At 4 and 20 °C, there were no differences in decay and mycelia development between the two Monilinia species. When temperature increased from 25 to 33 °C, the rates of fungal decay and mycelium development decreased. At 30 and 33 °C, M. fructicola decayed faster (0.94 and 1.2 cm days, respectively) than M. laxa (0.78 and 0.74 cm days, respectively) and could develop mycelia and produce sporodochia, whereas M. laxa failed at 33 °C. These results indicated that M. fructicola is better adapted to high temperatures, whereas M. laxa is better adapted to low temperatures. These results can be used to predict the relative importance of the two species during the season at a given site and to improve management strategies for brown rot in areas where both species are present.

Peach Brown Rot: Still in Search of an Ideal Management Option

“…Nowadays, in Spain, both Monilinia species (M. laxa (Aderhold and Ruhland) and M. fructicola (G. Winter) Honey) coexist in the field [4,47]. It can be inferred that M. laxa and M. fructicola have similar epidemiological physiognomies [57], considering such an inherent ecological coexistence. Incidentally, the epidemiology and management of M. fructicola have been most extensively studied, whereas the equally important M. laxa has received less attention [4].…”

“…Then, the brown rot disease cycle continues as indicated in Figure 5. However, when conditions (weather) are unfavorable, the infection can remain latent [72] until fruit maturity, the optimal time of disease development [8,57,73].…”

“…The estimated maximum temperature for lesion development is higher for M. fructicola (30 • C) than for M. laxa (10 • C), inferring that M. fructicola is favored by a warmer weather compared to M. laxa. Hence, Bernat et al [57] reported that M. fructicola is better adapted to high temperatures, whereas M. laxa is better adapted to low temperatures. These authors observed that, under optimal conditions, M. laxa is as aggressive as M. fructicola on peach fruits.…”

“…This is a pathological situation where the infected fruit can remain asymptomatic (latent), and visual decay symptoms only develop during the late ripening period and after harvesting [57], particularly when there is a favorable ambient condition. Most stone fruits with a latent brown rot infection caused by Monilinia do not develop visible signs of disease until their arrival at the market or consumers' home.…”

Epidemiología y control de la podredumbre parda del melocotón en postcosecha

“…Symptoms can appear in apparently healthy fruit after 3 to 4 days of incubation at room temperature. In a recent study Bernat et al (2017) have determined the effects of temperatures on M. fructicola and M. laxa fruit decay and mycelium development and the subsequent sporulation on peaches and nectarines. The rates of decay and mycelium development increased with temperature from 0 to 25 ºC for both Monilinia species (Bernat et al, 2017).…”