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• 1. [Article] Evaluation of methods of progeny testing in tall fescue seed production (Festuca arundinacea, Schreb.)

  Seventeen parental clones were selected, from 9,000 plants, on the basis of self-sterility, seed and forage yield potential using phenotypic ratings, crude protein and chromogen content. The parental clones ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of methods of progeny testing in tall fescue seed production (Festuca arundinacea, Schreb.) Author: Thomas, Johnny Ray Seventeen parental clones were selected, from 9,000 plants, on the basis of self-sterility, seed and forage yield potential using phenotypic ratings, crude protein and chromogen content. The parental clones were divided into two populations based on date of maturity. Group I was intermediate in maturity and had nine parental clones, while group E was early maturing and had eight parental clones. Six progeny testing methods (vegetative cuttings of parental clones, first generation selfed-seed (S₁ progeny), open-pollinated progeny, polycross progeny, seed from all possible single crosses, and selfed seed from the single-crosses or F₂ progeny) were compared using simple correlation coefficients between the progeny test and by comparing the rankings of the clones on the basis of each progeny test. The actual polycross performance was compared with the theoretical polycross performance or average of all possible single crosses, to see if equal and random fertilization occurred in the actual polycross. The results from the comparison of the six progeny testing methods indicated the vegetative cuttings of the parental clones and the single-cross progeny tests are the two most effective progeny testing methods when considering all four traits and both populations of plants. The open pollinated and polycross progeny tests were generally undesirable, because frequently there was no significant difference among their progeny. The S₁ progeny test was generally not desirable in group I; however, it appeared to be the most satisfactory test for seed yield when both populations of plants were considered. The results illustrate why there are inconsistencies in the literature concerning the effectiveness of the progeny testing methods. The effectiveness of the six progeny tests varied, to some extent, from trait to trait and for the two populations. For all four traits there was much less agreement among the six progeny tests in group E than in group I. In all four traits the F₂ generation showed a great inbreeding depression. The average of the single crosses was lower than the parents for tiller number, plant height, and 100 seed weight, but equalled the parents in yield per plant. The S₁ progeny were usually approximately equal to the average of the single cross progeny. The open-pollinated and polycross progeny were generally the highest for all four traits. The results from the comparison of the actual polycross with the theoretical polycross indicated that equal and random fertilization did not occur in the actual polycross. The more desirable clones appeared to contribute the majority of the pollen, since the actual polycross performance was usually greater than the theoretical polycross performance. Title: Evaluation of methods of progeny testing in tall fescue seed production (Festuca arundinacea, Schreb.) Author: Thomas, Johnny Ray Seventeen parental clones were selected, from 9,000 plants, on the basis of self-sterility, seed and forage yield potential using phenotypic ratings, crude protein and chromogen content. The parental clones were divided into two populations based on date of maturity. Group I was intermediate in maturity and had nine parental clones, while group E was early maturing and had eight parental clones. Six progeny testing methods (vegetative cuttings of parental clones, first generation selfed-seed (S₁ progeny), open-pollinated progeny, polycross progeny, seed from all possible single crosses, and selfed seed from the single-crosses or F₂ progeny) were compared using simple correlation coefficients between the progeny test and by comparing the rankings of the clones on the basis of each progeny test. The actual polycross performance was compared with the theoretical polycross performance or average of all possible single crosses, to see if equal and random fertilization occurred in the actual polycross. The results from the comparison of the six progeny testing methods indicated the vegetative cuttings of the parental clones and the single-cross progeny tests are the two most effective progeny testing methods when considering all four traits and both populations of plants. The open pollinated and polycross progeny tests were generally undesirable, because frequently there was no significant difference among their progeny. The S₁ progeny test was generally not desirable in group I; however, it appeared to be the most satisfactory test for seed yield when both populations of plants were considered. The results illustrate why there are inconsistencies in the literature concerning the effectiveness of the progeny testing methods. The effectiveness of the six progeny tests varied, to some extent, from trait to trait and for the two populations. For all four traits there was much less agreement among the six progeny tests in group E than in group I. In all four traits the F₂ generation showed a great inbreeding depression. The average of the single crosses was lower than the parents for tiller number, plant height, and 100 seed weight, but equalled the parents in yield per plant. The S₁ progeny were usually approximately equal to the average of the single cross progeny. The open-pollinated and polycross progeny were generally the highest for all four traits. The results from the comparison of the actual polycross with the theoretical polycross indicated that equal and random fertilization did not occur in the actual polycross. The more desirable clones appeared to contribute the majority of the pollen, since the actual polycross performance was usually greater than the theoretical polycross performance. Close