Selection under plant densities have been an issue of discussion but inconclusive. Troyer and Rosenbrook (1983) and Russell (1991) suggested that selection should be conducted under higher plant densities than normal growing condition to enhance grain yield in maize. Higher plant densities provide greater stress on the progenies and thus selected progenies were able to withstand stress. On the contrary, Fasoula and Fasoula (1997a) and Fasoulas and Fasoula (1995) proposed selection under isolation environment in honeycomb designs to avoid plant to plant competition, minimize soil heterogeneity, promote highest expression of genetic potential, enhance differentiation among lines and thus facilitate line selection. This study designed to compare moving circle selection, prediction criterion pc = x(x s - x] I S2p as proposed by Fasoula and Fasoula (1997b) and conventional visual grid selection (selection 1 plant out of each 19 plants in the same row). Grouped replicated R-49 honeycomb design and 40 replicated plants was used to screen 49 S7 inbreds. Moving circle selection identified highest number of diverse and good combine lines followed by PC and visual grid selection when tested in conventional plant spacing, 0.75 X 0.25 m. Top seven hybrids were derived from top-5 inbreds from moving circle selection while only 3 and 1 hybrids of PC and visual selection were included in top-7 hybrids.

English

0501|AGRIS 0501|AL-Maize Program

Juan Carlos Mendieta

CIMMYT Publications Collection