Vegetables - Disease Management          Pat Donald, MU  (573) 882-2716 
                                         Om Sehgal, MU (573) 882-7060

                               KEY
                          1 = Symptoms
                           2 = Control

PEPPER         

Seed rot and damping off (several fungi)     
   1.  Seed decay and pre-or post-emergence death of young plants. 
   2.  Soil application of metalaxyl (Ridomil 2E) will provide
       control of Pythium damping off and crown rot caused by
       Phytophthora capsici. Ridomil 2E must be applied to the soil
       before the plants are infected with Phytophthora to obtain
       satisfactory control. Note: Do not use Ridomil 2E for
       disease control in greenhouses.

Anthracnose (fungus)   Colletotricum piperatum and C. capsici 
   1.  Circular, tan or gray sunken lesions with pink dots on
       fruit, dark green margins, water-soaked and wrinkled. In   
       moist conditions, pinkish to yellowish masses of spores    
       appear on spots.  
   2.  Apply fungicide at 7-10 day intervals and more frequently in
       wet weather. Use fixed or neutral coppers. Maneb 80 1 1/2
       lb./A, Maneb plus Zinc F4 1.2 qt./A, or Maneb 75 1-1.2 lb./A.

Bacterial spot (bacteria)   Xanthomonas vesicatoria or X. campestris
   1.  Small green to dark brown raised lesions on leaves. Leaves
       turn yellow and drop. Fruit spots rough and blister-like.
       Bacteria are spread from plant to plant by splashing water. 
   2.  Apply copper materials at 7-10 day intervals, especially in
       wet weather. Fixed copper (50 percent WP); Kocide 101 WP or
       copper-streptomycin mixture. 

Blossom-end rot (physiological-non-parasitic) 
   1.  Caused by insufficient calcium when fruit are forming.
       Affected areas at the blossom ends are first water soaked,
       but soon become dry, light colored and papery.      
   2.  See tomato for control measures.

Cercospora leaf spot (fungus)   Cercosporia capsici 
   1.  Spots begins as small, circular and water-soaked areas.    
       Enlarge to gray or white spots with brown to reddish      
       margins. Centers of spots may drop out. Leaves drop off.   
   2.  Use disease-free seed of transplants. Apply foliar fungicide
       at 7-10 day intervals. Use fixed or neutral copper. See anthracnose.

Downy mildew (fungus)   Peronospora tabacini     
   1.  Mainly a seedling disease. White mold on the under surface
       of the leaves. Upper surface becomes yellowish, then brown
       & dies. Seedlings can be killed.  
   2.  Locate seedbeds away from tobacco seedbeds. Control weeds in
       nightshade family. Apply foliar fungicide in seedling stage at
       4-5 day intervals. Fixed or neutral copper. See anthracnose.
       
Viruses
Tobacco Mosaic virus (TMV), Cucumber Mosaic virus (CMV)   
   1.  Leaves are yellow-green, mottled and dwarfed. Plants are   
       dwarfed.  Fruit misshapen & mottled. Field symptoms can vary
       greatly, depending upon particular virus, strains of virus
       or combinations of viruses involved. Times of infection and
       other environmental conditions are also factors. Laboratory
       assays are necessary to determine particular viruses. 
   2.  Grower should consult seed catalog for current information
       on tobacco mosaic resistant varieties. However, these are
       not resistant to cucumber mosaic virus, so insecticides for
       aphid and other insect control must be used. Control weeds
       in the nightshade family which can be alternate hosts.  Consult
       the Plant Disease Clinic for more information on serological testing
       for virus identification provided by Dr. Om Sehgal.