Genetic Variation for Forage Yield and Quality among Grain Oat Genotypes Harvested at Early Heading
- L. B. Chapko ,
- M. A. Brinkman and
- K. A. Albrecht
Few studies have evaluated grain oat for forage yield and quality when harvested before heading, even though this is the current recommended practice when oat is used as a companion crop. The purpose of this research was to assess the amount of genetic variation that existed among grain oat (Avena saliva L.) genotypes for forage yield and forage quality when harvested at early heading (2–3 spikelets emerged from the boot), and to evaluate the relationship between forage yield, forage quality, and nine other agronomic traits. Sixty four elite grain oat genotypes were evaluated in the field on a Piano silt loam (fine-silty, mixed, mesic Typic Argiudoll) at Arlington, WI, in 1987 to 1989. There was substantial genetic variation for forage yield and forage quality traits as indicated by relatively large genotypic variance (σ2g) components. The σ2g for forage yield was six times as large as the genotype ✕ year interaction variance (σ2gy), while σ2g for acid detergent fiber (ADF) and neutral detergent fiber (NDF) were twice as large as the σ2gu. Although year ✕ genotype interaction mean squares were significant for all traits, relatively large σ2g and small σ2gy indicate that selection for forage yield and quality traits should be effective in this germplasm when based on multiple year evaluations. Tall, late genotypes typically had high forage yield and low forage quality. Phenotypic correlations between grain yield and forage yield (−0.29), and between grain yield and forage quality traits (−0.02 to 0.14) were small. Other agronomic traits had stronger associations with forage yield (r = −0.67 to 0.60) than with forage quality (r = −0.38 to 0.45). We concluded that grain genotypes must be evaluated individually before heading for forage quality to accurately assess their forage value.
Copyright © 1991.