§      Rhizopus on vinca (Catharanthus roseus)
§      Worker protection issue with the copper hydroxide

Stem rot caused by rhizopus is starting to show up. This pathogen has a wide host range including fruit and vegetable crops where it causes both pre- and post-harvest losses. In the greenhouse industry, it occurs most often on vinca and poinsettia and occasionally on African daisy (Gerbera jamesonii) and gloxinia (Sinningia speciosa).

Rhizopus infects all aerial plant parts, including blossoms. Disease may not develop in vinca until the canopy within the flats is well developed and dense. The pathogen creates lesions on stem tissue, growth beyond that point yellows and dies.

This is a fungal pathogen that produces spores in a ball-like structure protruding from the infected plant tissue on a stalk (sporangium). These reproductive structures are relatively large and can be seen in mass with the naked eye. In situations where the environment is particularly conducive, these sporulating structures create a black or gray fuzzy mass that can look similar to botrytis. Once the pathogen has begun to sporulate, large quantities of spores are easily dispersed through the air.

For assistance in diagnosing this pathogen please contact your local Extension agent or MSU Diagnostic Services (517-355-3504).

Worker protection issue with the copper hydroxide

Fungicides. Kocide and Junction

Tom Dudek
District Horticulture Agent

Recently it was brought to my attention that both the Kocide (various formulations) and Junction fungicide labels contain language in the Agricultural Use Requirements box that must be followed for seven days following application of either of these products. Greenhouse growers may use these products in the production of perennials or other outdoor flowering plants and should be aware that Worker Protection Standards rules for both Kocide (various formulations) and Junction require:

§      An eye flush container designed specifically for flushing eyes must be available at the WPS decontamination site for workers entering the area treated with either Kocide or Junction.

§      Notify workers of an application of Kocide or Junction by warning them orally that residues in the treated areas may be highly irritating to their eyes and to take precautions such as refraining from rubbing their eyes. If they get residues in their eyes, they should immediately flush their eyes using the eye flush container.

Also since these fungicides have a 24-hour REI any early entry workers that must go into the treated area prior to expiration of the 24-hour REI must wear protective eyewear in addition to the other personal protection equipment spelled out on the label.

Always read the label prior to applying a pesticide as changes do occur in language on the label.and this is a good example!