Recurrent Family Selection and Correlated Response in Nicotina tabacum L. I. ‘Dixie Bright 244’ ✕ ‘Coker 139’1

Abstract

Recurrent selection for increased alkaloids from a cross of two low alkaloid tobacco (Nicotiana tabacum L.) lines raised the population mean from the average of the two parents in the unselected population, to the high parent in one cycle of selection. Following two cycles of selection most families were above the high parent. A predicted decrease in yield of cured leaf in each cycle was obtained. The predominant genetic variance was additive, with little evidence of dominance or epistatic effects. The genetic variance following selection had not decreased from the initial population, and predictions were obtained for further continued progress from selection.