|Casler, M - UNIV WISCONSIN|
|Moore, Kenneth - ISU|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 29, 1995
Publication Date: N/A
Technical Abstract: Lignin and associated phenolic acids are inversely related to digestibility of forages. They are also involved in resistance of plants to stresses such as insect and disease attack and resistance to cold temperatures. Thus, selection for high digestibility or low lignin concentration may reduce the ability of forages to survive stresses. We monitored field survival of orchardgrass (Dactylis glomerata L.), smooth bromegrass (Bromus inermis Leyss.), and switchgrass (Pancium virgatum L.) over 3 years in Nebraska, Iowa, and Wisconsin. Within orchardgrass, smooth bromegrass, and switchgrass, genotypes selected for one cycle of high or low digestibility did not differ in survival. However, after 3 years, survival of switchgrass selected for three cycles of high digestibility was reduced to 65% compared with 81% in the base population. Thus, our data suggest a threshold effect of selecting for improved digestibility before field survival is adversely affected.