Gary W. Moorman, Professor of Plant Pathology
|BACTERIAL LEAF SPOT||Water-soaked spots with yellow halos spread rapidly on leaves. Centers of the spots fall out under wet conditions.||Pseudomonas cichorii||Avoid overhead watering. Discard infected plants.|
|PYTHIUM ROOT ROT||Cuttings have poor root systems and yellow leaves. Leaves of established plants yellow and die. Stems have a mushy black rot.||Pythium||Plant in a potting mix free of pathogens. Apply mefenoxam, potassium salts of phosphorus acid, dimethomorph, or etridiazole to protect healthy plants.|
|RHIZOCTONIA STEM ROT||Stems at the soil level are killed. Under wet conditions, a fine webbing of fungal growth can be observed on the soil surface near the infected stems.||Rhizoctonia||Plant in a potting mix free of pathogens. Apply iprodione as a spray directed at the base of the stems or PCNB as a drench.|
Active Ingredients and Trade Names of the Chemicals
|FRAC Group No.||Risk Level||Class||Active ingredient||REI Restricted Entry Interval||Trade names (EPA Reg. no.)|
|2||3||Dicarboximide||iprodione||12||Chipco 26GT (100-1138), Chipco 26019 (264-481), Iprodione (51036-361), Sextant (51036-361-59807)|
|4||3||Acylanine||mefenoxam||0||Subdue MAXX (100-796)|
|hydrocarbon||PCNB||12||Revere (400-407-10404), Blocker (5481-211), Terraclor (400-399), Defend (5481-444-1001)|
|Thiadiazole||etridiazole||12||Truban (58185-7), Terrazole (400-416)|
Fungicides and Fungicide Resistance Management - Certain fungicides, usually systemic fungicides, are said to be 'at risk' to the development of resistance if they are used repeatedly. See the Risk Level in the above table (1 = low risk; 3 = high risk). The Fungicide Resistance Action Committee has developed a numbering system in which chemicals with the same FRAC Group number have the same mode of action (See http://www.frac.info/frac/index.htm ). It is recommended that chemicals at high risk be used sparingly and in rotation or mixed with chemicals with different modes of actions (different FRAC number).
Notice: The user of this information assumes all risks for personal injury or property damage.
Warning! Pesticides are poisonous. Read and follow all directions and safety precautions on labels. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Dispose of empty containers right away, in a safe manner and place. Do not contaminate forage, streams or ponds.
Issued in furtherance of Cooperative Extension work, Acts of Congress, May 8 and June 30, 1914, in cooperation with the U. S. Department of Penn State College of Agricultural Sciences research and extension programs are funded in part by Pennsylvania counties, the Commonwealth of Pennsylvania, and the U.S. Department of Agriculture.
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