EFFECTIVENESS OF SEVERAL SELECTION METHODS FOR GRAIN YIELD IN TWO F2 POPULATIONS OF SPRING WHEAT
Visual head selection by three selectors, head weight, harvest index, and random selection were evaluated for selecting high-yielding plants in two F2 populations of spring wheat (Triticum aestivum L.). Forty F2 lines of two crosses for each selection method were evaluated for yield performance in F4 during 2 yr. There was no advantage of any of the selection methods over random selection in the lower-yielding cross 1 and no advantage of the harvest index and head weight methods over visual selection in both crosses. Visual head selection produced more late-heading, tall plants, and was the most effective method in selecting for yield in cross 2. Harvest index tended towards the selection of lines with short height in cross 2. A larger number of the top 15% of F4 lines were from the high yielding cross 2, and selectors 1 and 2 chose the greatest number of superior lines.Key words: Selection methods, head weight, harvest index, grain yield, spring wheat, visual head selection.