Exemplar Mucor Growth on Strawberry

I was holding some strawberry fruit a few weeks ago to check on a pathogen for a local grower (it's very likely anthracose, but more to come on that account), and of course this being late season had a lot of leak rot showing up.

Can't help myself here folks, but this one is a beauty!  The undisturbed conditions of the moist chamber let the fungus really blow up and spread out.  Again, as readers of this blog will know the sticky wet appearance of the sporangiophores tell us this is very likely to be Mucor rather than Rhizopus. 

The leak rots are difficult to manage in the field, and in fact the only thing strawberry growers have available are cultural controls. The UC IPM guidelines instruct us that to minimize leak issues, handle fruit with care at all times. Remove all ripe fruit from the field at harvest and avoid packing overripe fruit. Be sure when fruit is being picked that the entire fruit is removed from the stem, not leaving behind the fleshy receptacle of the fruit as it can serve as a site for invasion by fungus.

Mucor rot on strawberry. Note the fluffy appearance and wet sticky aspect of the sporangiophores. The paper towel used to be white, but has been completely stained with juice leaking out of the fruit.

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