A comparison of progeny testing methods and estimates of combining ability for seed yield and associated variables in tall fescue (Festuca arundinacea, Schreb.)

Graduation date: 1964Eight genotypes of tall fescue were selected from a plant\ud population consisting of 9000 individuals. Selection was based on\ud early maturity, self-sterility, seed and forage potential, and nutritive\ud value.\ud Parental clones, single cross, open pollinated, self pollinated\ud and polycross seeds were organized into a randomized block experiment\ud with five replications each of which contained 63 entries with\ud ten plants to the entry. The distance between entry rows was three\ud feet; plants within the entry were planted one foot apart. The experimental\ud nursery was planted on October 11, 1961, at the Hyslop\ud Agronomy Farm, Corvallis, Oregon. Alta and Kentucky 31 varieties\ud were used as checks. Parchment bags were used to secure\ud information on self sterility and seed production. Height, maturity,\ud disease incidence, number of culms per plant, panicles not harvested\ud and forage yield were also evaluated. Griffing's model 1, experimental\ud method 4, was used to test both general and specific combining\ud ability. Simple correlation coefficients were calculated to measure\ud the association between characters and between progeny testing\ud methods within characters.\ud The height of F₁ progenies was positively correlated with the\ud height of both the mean of the parents and the largest parent. Height\ud was also correlated with the number of culms per plant and the stage\ud of maturity before harvesting.\ud The stage of maturity of the single crosses was positively\ud correlated with the stage of maturity of both the mean of the parents\ud and the largest parent. Either polycross or open pollination may be\ud used for evaluating maturity with comparable results.\ud Although there was an incidence of Helminthisporium\ud dyctioides, it was not serious enough to affect markedly the general\ud performance of the plants in the nursery.\ud The number of culms per plant for single crosses was negatively\ud correlated with the number of culms for both the mean of the\ud parents and the smallest parent. The number of culms per plant was\ud also correlated with seed yield. From parents to S₁ there was a\ud reduction in the number per plant