Inheritance of Root Traits in an Interspecific Cross of Capsicum annuum × C. chinense in the Presence of Low Moisture

ABSTRACT

Productivity of hot pepper (Capsicum annuum L.) is constrained when available moisture is not adequate. Capsicum genotypes with deep, strong roots enable plants to take up a higher volume of water when moisture is lacking, resulting in a more favorable plant water status. Little information is available on the genetic inheritance of root traits in peppers. The genetic components governing expression of root traits under low moisture were studied through six-generation mean analysis in an interspecific cross of IHR 3453 (Capsicum annuum) × IHR 4502 (C. chinense) of contrast root traits. The six generations (30 P₁, 30 P₂, 30 F₁, 247 F₂, 43 B₁, and 47 B₂) were developed and evaluated for root traits under low available moisture. Overall, root traits and shoot dry weight are complex in inheritance; additive and nonadditive components were important, indicating that reciprocal recurrent selection is the most effective breeding method for improving these traits. The dominance component (h) was highly significant and predominant in controlling most traits, except for root length. High heritability and high genetic advance over the mean indicate that selection is effective; however, it needs to be postponed to later generations. Recurrent selection, bulk pedigree, and single-seed descent methods were the most efficient strategies for improving root traits in Capsicum.

KEYWORDS:

• Capsicum spp
• dominance
• gene action
• generation mean analysis, heritability