Publication Date
1989
Description
Leaf diseases of orchardgrass (Dactylis glomerata L.) caused by Mastigosporium rubricosum (Dearn. and Barth.) Nannf. (eyespot), Rhyncosporium orthosporum Caldwell (scald), and Cercosporidium (Scolecotrichum) graminis Fckl. (leaf streak) are widely distributed in the seed-producing area in Oregon (Sprague, 1950). These diseases may occur alone or in combination and are more severe when weather is cool and wet. Symptoms develop in February and can extend through June. In most years, all three diseases can be found on individual plants in April and May. The diseases cause premature death of leaves, but not defoliation. When severe on the upper leaves (the flag leaf and the few leaves below), it is presumed they reduce seed yield. The economics of grass seed production limits a grower's investment to control diseases because the crop is considered to be of low economic value. The most successful disease controls are those incorporated into usual farming practices, including improved growing conditions for the host, or modifying cultural practices. Fungicides with preventative, curative, or eradicative properties offer opportunities to control leaf diseases. The objective of this investigation was to study the effect of chlorothalonil, propiconazol, and captafol on seed yield and disease control. The number and timing of fungicide applications were also investigated.
Citation
Welty, R E., "The Effect of Fungicide Application on Seed Yield of Dactylis glomerata" (2025). IGC Proceedings (1989-2023). 22.
https://uknowledge.uky.edu/igc/1989/session5/22
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
The Effect of Fungicide Application on Seed Yield of Dactylis glomerata
Leaf diseases of orchardgrass (Dactylis glomerata L.) caused by Mastigosporium rubricosum (Dearn. and Barth.) Nannf. (eyespot), Rhyncosporium orthosporum Caldwell (scald), and Cercosporidium (Scolecotrichum) graminis Fckl. (leaf streak) are widely distributed in the seed-producing area in Oregon (Sprague, 1950). These diseases may occur alone or in combination and are more severe when weather is cool and wet. Symptoms develop in February and can extend through June. In most years, all three diseases can be found on individual plants in April and May. The diseases cause premature death of leaves, but not defoliation. When severe on the upper leaves (the flag leaf and the few leaves below), it is presumed they reduce seed yield. The economics of grass seed production limits a grower's investment to control diseases because the crop is considered to be of low economic value. The most successful disease controls are those incorporated into usual farming practices, including improved growing conditions for the host, or modifying cultural practices. Fungicides with preventative, curative, or eradicative properties offer opportunities to control leaf diseases. The objective of this investigation was to study the effect of chlorothalonil, propiconazol, and captafol on seed yield and disease control. The number and timing of fungicide applications were also investigated.
