F3 Selection Research Articles

The influence of systematic micro-environmental variation on individual plant yield within selection plots

Moving average and polynomial response surfaces were used to estimate systematic micro-environmental variation within four different F3 selection environments. At low density the response surfaces were efficient in estimating systematic variation. At high densities random variation due to intergenotypic competition predominates. It is concluded that the two major factors rendering single plant selection for yield inefficient are competition within selection plots and genotype-season interactions between the selection and test generations.

Empirical Evaluation of Single‐Plant and Family Selection Strategies in Wheat1

Random F3 families from the cross of two high‐yielding short‐statured spring wheats (Triticum aestivum L.) ‘Anza’ and ‘Bluebird‐2’ were space‐planted in two blocks in a field planting. From each F3 family, two to five of the best appearing plants from one block and five random plants in the second block were selected to study four selection strategies. Grain yields of the F3 plants were obtained and 36 random families, each having three random and two visually selected lines, were studied in the F4 in field trials at two locations using the commercial seeding rate. The F3 selection strategies and F4 yield results, given as percentages over the random F4 mean yield for the random and visually selected progenies, respectively, were as follows: (1) individual selection, 0.33 selection intensity, 4.21 and 4.73%; (2) within family selection, best plant in each family selected, 2.43 and 2.87%; (3) family selection, 0.33 selection intensity, 1.01 and 5.52%; and (4) combined family and within family selection, 0.33 selection intensity for families with the best plant selected within families, 3.56 and 7.57%. Three‐stage selection using (1) visual selection of plants, (2) selection of families on the basis of the mean of yields of visually selected plants, and (3) selection of best plants within selected families appears to be an effective and easily applied strategy worthy of further evaluation.