Genotypic and Environmental Effects on Grain Yield and Quality of Oat Grown in North Dakota

the whole oat that is recovered as groat after dehulling. Groat percentage has long been recognized as an imporThe grain yield and quality determine much of the value of an oat tant indicator of oat quality (Love et al., 1925; Stoa et (Avena sativa L.) crop to the producer. This study investigated effects al., 1936; Atkins, 1943; Bartley and Weiss, 1951). Peek of genotype and environment on grain yield and quality. Twelve oat genotypes were grown during 3 yr at four locations in North Dakota and Poehlman (1949) considered test weight to be a where detailed environmental data were being collected. Grain yield, more valuable oat quality evaluation tool than groat test weight, groat percentage, groat weight, and groat composition percentage because hand-dehulling of oat was consid(protein, oil, -glucan, and starch concentrations) were evaluated. ered too tedious. Stoa et al. (1936) suggested that early Results were subjected to analysis of variance and influences of envimaturing oat cultivars were superior in groat percentronmental factors were evaluated by correlation analysis. Analysis of age, and rust susceptible lines were generally higher in variance suggested that grain yield, groat starch, and ash concentrapercent hull. These conclusions were also supported by tions were more strongly affected by environment than by genotype. the findings of Bunch and Forsberg (1989). The studies Test weight, groat percentage, groat weight, protein, and -glucan of Bartley and Weiss (1951) indicated strong environwere about equally influenced by environment and by genotype, mental effects on groat percentage and demonstrated whereas groat lipid was more strongly influenced by genotype. Signifipositive correlations between groat percentage and cant environment genotype interactions for all characteristics were attributed to differential resistance of genotypes to crown rust (caused yield, test weight and kernel weight. Youngs and Shands by Puccinia coronata Corda var. aveneae W.P. Fraser & Ledingham) (1974) demonstrated that tertiary kernels had a higher infection. Environments severely affected by crown rust produced groat percentage than primary and secondary kernels, grain with lower test weight, groat weight, and groat percentage in although Palagyi (1983) found that genotypes with susceptible genotypes. Correlation analyses suggested that warm, higher levels of tertiary kernels had lower groat percentbright (high solar radiation) spring weather, and cooler summer weather age. He suggested that tertiary kernels compete with without excessive rains during grain filling generated the best oat primary and secondary kernels for assimilate, preyields with high quality grain. venting them from filling properly. Very little information is available concerning the control of oat groat weight, although one study (Gullord and Aastveit, 1987) C most commonly used to describe indicated significant genotype environment interacoat quality include test weight, groat percentage, tions for the trait. groat weight, and groat composition. The major groat Among the compositional components of oat, protein compositional characteristics relating to quality include concentration often is ranked highly in importance bethe protein, oil, and -glucan concentrations. Plant cause of its nutritional significance. Oat groats may conbreeders strive to generate cultivars that will yield well tain from 124 to 244 g kg 1 protein, and this protein and produce consistently high quality grain over a wide is of higher nutritional quality than most other grains range of environments. A relatively small amount of (Peterson, 1992). Studies have shown genotypic and eninformation is available in the literature describing the vironmental effects on oat protein concentration (Jeneffects of environment and genotype on oat grain yield kins, 1969; Forsberg et al., 1974; Saastamoinen et al., and quality. 1989). In particular, nitrogen supply strongly affects oat Test weight is the most commonly used method to protein concentration (Ohm, 1976; Welch and Yong, evaluate oat quality (Forsberg and Reeves, 1992). Test 1980; Welch et al., 1991; Humphreys et al., 1994; Jackson weight is a measure of the density of oat grains as they et al., 1994). are packed into a given volume. It is reported to be Oat contains much higher oil concentrations than do affected by kernel and groat size, groat density, hull other small grains (Youngs, 1986). Higher oil content thickness and length, and groat percentage as well as is an advantage for animal feeding because of its higher the presence of awns, diseases, and tertiary kernels caloric content. However, in food applications, higher (Murphy et al., 1940; Atkins, 1943; MacKey, 1959; Forsoil concentrations are deleterious because of their poberg and Reeves, 1992). Several studies have reported tential for rancidity and production of off-flavors. Studgenotype environment interaction for oat test weight ies have indicated that both genotype and environment (Bartley and Weiss, 1951; Gullord and Aastveit, 1987). affect groat oil concentration (Brown et al., 1966; SaasGroat percentage is a measure of the proportion of tamoinen et al., 1989; Welch, 1975; Humphreys et al., 1994). Cooler growth environments have been reported D.C. Doehlert, USDA-ARS Hard Red Spring and Durum Wheat to stimulate oil accumulation in groats (Beringer 1971, Quality Lab., Harris Hall, North Dakota State Univ., Fargo, ND 58105; M.S. McMullen and James J. Hammond, Dep. of Plant Sciences, Saastamoinen et al., 1989). Negative correlations beLoftsgard Hall, North Dakota State Univ., Fargo, ND 58105. Received tween protein concentration and oil concentration among 1 June 2000. *Corresponding author ([email protected]. different oat genotypes have been reported (Brown et edu). al., 1966; Forsberg et al., 1974). This relationship has been disputed (Youngs and Forsberg, 1979), and cultiPublished in Crop Sci. 41:1066–1072 (2001).