A quick update on Mummy Berry Development:
We want
to share an important update regarding our Highbush Monilinia
monitoring. As of May 26, all the mummy berries have dried up and cannot
release ascospores (Figure 1). What we see now, are the symptoms of ascospore damage
which were released earlier in the season.
Figure 1(above). Dried mummy
berries.
In early maturity varieties, shoot blight symptoms such as drooping of affected shoots, followed by brownish purple discoloration of the upper sides of the midribs and lateral veins of affected leaves and flower cluster blight can be observed (Figure 2, and 3).
Figure 2 and 3(above). Twig blight
caused by Monilinia.
The tufts of grayish conidia appear along the
petioles, midribs of affected leaves, and on the infected peduncle or flower
pedicels (Figure 4). These conidia that are forming on the diseased leaf shoots
and flower clusters will now be spread further by bees, flies, and wind to open
flowers where they will grow down the flower style and eventually form a mummy
berry.
Figure 4(above): Grayish mycelium
of the fungus on the petioles.
- Most
of mid and late maturity varieties are clean but regular scouting of the
fields is highly recommended to help plan for next years mummy berry
management.
- Usually,
fungicide sprays targeted to prevent these flower infections are not cost
effective but can be practiced. The pruning of branches is not recommended
but the easiest way to prevent further conidial spread would be to simply
pick off diseased leaf shoots and flower clusters and drop them to the
ground or collect them in a bag. This would limit the spread of conidia
that are present now.
