Recurrent Selection within a Population from an Interspecific Peanut Cross
1986
Guok, H. P. | Wynne, J. C. | Stalker, H. T.
A transfer of genes from closely related species can be useful to improve commercial crop cultivars. The objectives of this study were to evaluate three cycles of selection for yield and to determine the potential of future progress of selection in a peanut (Arachis hypogaea L.) (2n = 40) ✕ A. cardenasii Krap. et Greg. nom. nud. (Iₙ = 20) population. Resistance to late leafspot [Cercosporidium personatum (Berk, and Curt.) Deighton] was measured for selected families. Ten families selected for high fruit yield and large fruit size from the segregates of the original cross were randomly intermated to form the initial population. After two cycles of recurrent selection using S₁ testing, response to selection was evaluated by comparing the individual parents of the three cycles (C₁, C₂, and C₃) in four environments during 1982 and 1983. Two cycles of selection resulted in an increase in fruit yield of 210 ± 70 kg ha⁻¹ per cycle. Seed weight, meat content (proportion of total seed weight to total fruit weight in %), and extra large kernels (% seeds that are retained on a 0.85- ✕ 2.54-cm screen) increased significantly, while fruit length and other kernels (% seeds that pass through a 0.60- ✕ 2.54-cm slotted screen) decreased significantly over the two cycles of selection. Little variability was found among the lines after the second cycle. Genetic variability for resistance to late leafspot existed among the parents of the three cycles. The results indicate that the diploid species of Arachis contain genes that can be utilized to improve yield as well as other traits such as disease resistance of the cultivated peanut.
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