Heritability Estimates for Grain Yield in Oats (Avena sp.)
1971
Pfahler, P. L.
Narrow sense heritability values were determined from actual selection response and in standard units using 94 populations grown in replicated trials in 1964, 1965, 1966, 1967, 1968, and 1969 at Gainesville, Florida. Eighty-nine of the populations were homogeneous and homozygous lines with diverse genetic backgrounds derived from crosses involving Avena sativa L. and A. byzantina C. Koch. Five were recommended varieties. Heritability values by selection response were determined using three levels (upper 10, upper 25 and upper 47 of the 94 populations) of selection and the mean of the 94 populations as a reference point for response. Over all levels of selection, the values ranged from _.55 to .76 for individual year comparisons. When individual years were compared to the 6-year mean, the range was _.05 to .87. No consistent differences were found as a result of selection level although in a few cases selection of the upper 25 instead of the upper 10 resulted in higher values. Heritability values determined in standard units ranged from _.05 to .63 when individual years were compared and from .11 to .67 when individual years were compared to the 6-year mean. In general, values between individual years and the 6-year mean were equal to, or higher than, those between individual years. A hypothetical selection and testing procedure was designed in which the yields of 1, 2, 3, 4 and 5 years were combined at random to determine the effect of the number of years tested on the heritability values relative to the 6-year mean. No substantial or consistent changes in values were obtained as the number of years tested was increased.
显示更多 [+] 显示较少 [-]