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G90-970 Summer Patch And Necrotic Ring Spot, John E. Watkins, Robert C. Shearman, Terrance P. Riordan

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes the causes, predisposing conditions, and symptoms of summer patch and necrotic ring spot, and provides recommendations for their control.

Research since 1980 has resulted in considerable progress in identifying causes of the "patch"-type disease of turfgrass. Two of the most destructive patch diseases of turfgrasses are summer patch and necrotic ring spot.

Both summer patch and necrotic ring spot are present in Nebraska turfs. Unfortunately, necrotic ring spot and summer patch cause identical symptoms and cannot be distinguished in the field, and identification in the laboratory is time-consuming (3-6 months) and laborious.

G90-980 Rose Mosaic And Rose Rosette Diseases, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

The rose mosaic and rose rosette diseases may cause a variety of symptoms, including reduced plant vigor and flower quality. Early detection is essential to control.

Roses have been cultivated as an ornamental for 4,000 to 5,000 years and now are distributed worldwide. Rose virus and virus-like diseases occur wherever roses are grown. Since roses are vegetatively-propagated through budding or grafting, these pathogenic agents are easily spread during propagation. Infection by virus or virus-like agents may cause a wide variety of symptoms. These can range from latent, symptomless infections to mosaic leaf patterns and distortions, severely distorted canes, and finally, …

G90-979 Powdery Mildew Of Roses, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Cause, symptoms of and conditions for powdery mildew are covered, as well as ways to control the disease.

The rose is one of the most popular flowering ornamentals in the world. It is thought to have first been cultivated 4,000 to 5,000 years ago in northern Africa. Today it is a favorite ornamental for landscapes, as well as the most important commercial cut flower.