Evaluation of Honeycomb Selection for Single Plant Yield in Durum Wheat1

Abstract

Fasoulas' (1973) honeycomb design was used to select for high and low yield among single F2 plants in three crosses of durum wheat, Triticum turgidum L. var. durum, each planted at interplant spacings of 30 and 60 cm. Response to selection, measured by yield of replicated F3 bulks of F4 lines, was significant for all three crosses when grown at 60 cm spacing and for two of the three crosses when grown at 30 cm. Significantly greater response in the downward than in the upward direction was observed in one cross. Correlations between 1979 single plant yields and 1980 plot yields in the one cross where progeny of all plants were tested indicated i) that selection was slightly more effective at wider spacing, ii) that Fasoulas' method was marginally superior to mass selection based on unadjusted single plant yields, and iii) that heritability of single plant yield was 13 to 17%. Average response to single plant selection for yield was 4% of the mean yield in solid seeded plots.