Pasture - Disease Management     Craig Roberts, MU  (573) 882-2001
                                 Jeanne Milhail, MU  (573) 882-1471

                               KEY
                          1 = Symptoms
                    2 = Registered Pesticides
                           3 = Remarks

Ergot   Claviceps purpurea
   1.  Seeds are replaced by horn-shaped, purple-brown fungal
       sturctures called sclerotia or ergots. The ergots contain
       alkaloids which are highly toxic to humans and livestock.
   2.  
   3.  Remove plant debris by plowing or burning. Control infected
       weeds in the surrounding area. Rotate to non-susceptible
       crops for two years.

Rust   Puccinia spp. Uromyces spp.
   1.  Orange to brown elliptical lesions on leaves and stems. With
       heavy infections, reduced leaf area will result in lower
       seed yield.
   2.  None registered.
   3.

Seed decay and seedling disease   Pythium, Fusarium and other fungi
   1.  Poor stand establishment. Seed fail to germinate or seed
       germinate and the roots decay.
   2.  Apron-FL 0.75 to 1.50 fl oz./cwt, Apron 25 W 1-2 oz/cwt,
       Apron Dry 3-4 oz/cwt, Captan 300, 30-DD 6.5 fl oz/cwt,
       Captan 400 5-8.25 fl oz/cwt, Thiram 30 26.5 fl oz/cwt, 42-S
       8 oz/cwt.
   3.

Seed or leaf gall nematodes   Anguina spp.
   1.  Dying small plants, wrinkled and twisted leaves of young
       plants, reduced and irregular heads, and presence of cockles
       in the seed head. 
   2.
   3.  Destroy plant debris. Use clean seed.

Other nematodes
   1.  Above-ground symptoms depend on the level of infestation. At
       high levels there may be stunting, yellowing, and an
       unthrifty appearance. Yields are reduced. Symptoms may be
       confused with mineral deficiency, drought, herbicide injury,
       or soil-borne diseases. Symptoms occur in oval patches or
       may be spaced erratically throughtout the field. Root
       systems are severely restricted and may contain lesions,
       swellings, or galls.
   2.  
   3.  Control options depend on species present. Species I.D. can
       be done by the Nematology Laboratory (573) 882-2716.

Smut   Sorosporium spp. Sphacelotheca spp. Tilletia spp. Ustilago
spp.
   1.  Grain may be replaced by dark masses of fungal spores. For
       some pathogen species, floral structures or leaves are
       covered with dark-brown spores.
   2.  None registered.
   3.  Seed treatment may give control. Treatment depends on
       whether the smut is contaminating the seed surface or is
       contained within the seed.

Tarspot   Phyllachora spp.
   1.  Small black spots on the leaves appear to be small droplets
       of tar.
   2.  None registered.
   3.