Help requested - Brunsvigia josephinae rot <:-(

Hans-Werner Hammen
Sun, 16 Oct 2011 14:21:06 PDT

Hello Ken, to me, this looks pretty much like a secondary infection from red blotch (Stagonospora curtisii) originating from an infestation through bulb scale mites (Steneotarsonemus laticeps). This would mean, that antifungal treatment is not the key, in order to cure the bulb. The mites hide between the scales where-ever these are not firmly closed. These animals are barely visible with the unarmed eye, and you can only confirm my diagnosis, by removing small pieces of the decaying matter usuing tweezers, and inspect the fragments under a strong magnifier-lense or a Microscope. Against bulb scale mites in Hippeastrums, I use Dimethoate (400g/L in Cyclohexanon, for example Rogor) - there is a large number of brands of the same formula available; at 2.5 mL per Liter water. Generally I add to the water 20 g/l Alum = KAl(SO4)2 x 12 H2O, as a mild desinfection agent. In this case, the solution should not in abundance soak deeply into the soil.
> Date: Sun, 16 Oct 2011 11:41:54 -0700
> From:
> To:
> Subject: [pbs] Help requested - Brunsvigia josephinae rot <:-(
> I discovered some rot in the upper old leaf bases of this Brunsvigia josephinae.  It bloomed in August and September this year ... and we had a freak heavy rainstorm then followed by warm weather ... which I suspect is responsible for this rot.  Any suggestions on treatment?  Sulphur?  A fungicide?
> I hate to lose this treasured bulb ... a 16 year investment from seed.
> Ken Blackford
> San Diego

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