CONTRIBUTION OF GROWTH RATE AND HARVEST INDEX TO GRAIN YIELD IN F₉-DERIVED LINES OF OATS (AVENA SATIVA L.)

Abstract

The contributions of growth rate (GR) and harvest index (HI) to grain yield (GYD) were studied using 1200 F9-derived lines of oats tested for 2 yr. Heritability ranged from 20 to 40% for GYD, GR, and HI. Genotypic correlations of GYD with GR were ca. 0.7 and with HI ca. 0.3. More than 95% of GYD variation was due to GR and HI. An increase of 0.1 g/day/plot GR would result in a 14% increase in GYD, and a 5% increase of HI would cause an 18–19% increase in GYD. GR was positively correlated with heading date and plant height, and negatively with HI.

Direct and indirect selection for grain yield in oats (avena sativa L.)

“…These results support the suggestion of TAKEDA et al (1979TAKEDA et al ( , 1980 that the inherent yielding capacity of oat cultivars for midwestern USA may be increased by increasing vegetative growth rate.…”

Three selection strategies that utilize recurrent selection to increase protein yield in oats

“…Estimates of heritability for heading date and plant height were high, unchanged over cycles, and in agreement with previous reports Takeda et al, , 1980. While genetic vari ances for heading date declined in the HG and HP lines of descent, the reductions were not sufficiently large to impede response to future selection.…”

“…Heritability estimates also declined from CO to C3, but they ranged from 0.46 to 0.67, values that are larger than those reported previously Takeda et al, , 1980.…”

“…Heritabilities for bundle weight were higher than those previously reported Takeda et al, , 1980 Inclusion of these traits in a multiple trait selection strategy likely would decrease the response in groat-protein yield, but probably it would improve the overall breeding value of the germplasm pools for variety development.…”

“…Correlations involving grain yield coincide closely with those obtained for protein yield. That is, grain yields are consistently and positively associated with harvest index, bundle weight, seed weight, and height (Gullord, 1980;Takeda et al, , 1980). Within sativa germplasm, protein percentage is negatively associated with height, harvest index, grain yield, groat percentage, and bundle weight Forsberg et al, 1974;Gullord, 1980;.…”