Main symptoms on berries



The Penicillium spp. can mount several aspects on grape berries:

  • A blue-green rot

Penicillium expansum Mostly , and a few other species of Penicillium spp. are responsible for a soft, wet rot on grape berries, the color of which is slightly dark blue on black grape varieties (figure 1), and beige to reddish on white grape varieties (figures 2 and 3). It should be noted that the rotten tissues gradually become covered with spore-bearing pads, the color of which fluctuates over time (figures 4 and 5). First whitish, they turn blue ( blue rot , blue mold) or even gradually green and darken.

  • Presence of various molds on and in the heart of the bunches

The fruiting bodies of many  Penicillium spp. develop on (Figure 7) or near (Figure 8) and / or in the heart of botrytis clusters (Figures 9 to 11), this following their secondary development. Thus, we can observe white to colored colonies that spread over gray mold.

Note that the development in the heart of the clusters of a Trichoderma sp. is sometimes found. Its fruiting bodies causing blue-green mold (Figure 12) should not be confused with those of Penicillium spp .

Last change : 04/19/21
Penicillium10
Figure 1
Penicillium31
Figure 2
Penicillium30
Figure 3
Penicillium11
Figure 4
Penicillium33
Figure 5
Penicillium24
Figure 6
Penicillium_bot2
Figure 7
Penicillium36
Figure 8
Penicillium_bot3
Figure 9
penicillium_4_
Figure 10
penicillium_5
Figure 11
Trichoderma1
Figure 12