Variability and correlation of iron-deficieney symptoms in a sorghum population evaluated in the field and growth chamber

Summary

One hundred S₁ families from a random-mating sorghum [Sorghum bicolor (L.) Moench] population (NP21R) were rated visually for differences in iron-deficiency chlorosis in the field and in a growth chamber. Heritabilities on a family-mean basis were estimated far the first (0.63 ± 0.15), maximum (0.79 ± 0.15), and average chlorosis rating (0.84 ± 0.15) recorded over S₁ families in the field. Heritability on an individual plant basis was estimated for the average chlorosis ratings in the growth chamber (0.65 ± 0.16). Phenotypic and genotypic correlations were large and negative between field chlorosis ratings and yield or yield-related traits, which indicated that the severity of chlorosis was an important factor in determining S₁ family agronomic performance. Correlations between chlorosis traits over all S₁ families in the growth chamber and field generally were small and nonsignificant.