Evaluation of Self and Polycross Progeny Testing in Birdsfoot Trefoil (Lotus corniculatus L.) for Forage and Seed Yield

Abstract

Self and cross fertility, forage and seed yield of parents, self (SI), and polycross (PX) progenies were measured m a selected and an unselected population of birdsfoot trefoil {Lotus comicuiatus L.). Self fertility was significantly less than cross fertility in both populations. In a field planting SI progenies had lower forage yield in 1979 and 1980 and seed yield (relative to the parents) was less in the selected population tban the unselected in 1979. All correlation coefficients between years and progenies were non-significant for forage yield but the parentspolycross progeny correlation was significant for seed yield in the selected population. Percentage survival of plants after cutting in 1980 was higher m the selected population, and the parents and PX progenies survived better than Si progenies in both populations. The better performance of the selected population may be due, in part, to higher frequency of favorable genes resulting from four cycles of recurrent selection. SI progeny testing does not appear to be worthwhile in birdsfoot trefoil because of low self fertility and the reduced vigour of the progeny.Self (SI) and polycross (PX) progeny testing methods have been widely used in forage breeding to evaluate parental genotypes (BusHicE et al. 1972). Early data indicated that both SI and open-pollinated (OP) progenies can be used to evaluate genotypes of alfalfa {Medicago sativa L.) for forage yield (WILSIE 1951). However, DAVIS (1955) found a higher parent-progeny correlation for SI than for PX and concluded that SI progenies were superior to PX progenies for evaluation of forage yield. In a later comparison of PX and SI progeny testing, BusBiCE et al. (1974) found that neither method was effective in increasing forage yield in alfalfa. MACDONALD et al. (1952) compared SI and OP progenies for forage yield and plant height in bromegrass {Bromus inermis Leyss) and concluded that OP progenies consistently gave higher parent-progeny correlations than did SI progenies. Studies in red clover {Trifolium pratense L.) and in bromegrass indicated that PX progeny testing was effective for breeding for persistence and seed yield, respectively (TAYLOR et al. 1968, KNOWLE.S et al 1970. To our knowledge, a similar comparison of SI and PX progeny testing in birdsfoot trefoil has not been reported.Several studies have indicated that cross fertility IS higher than self fertility in birdsfoot trefoil (TOME and JOHNSON 1945, MCKEE 1949, SEANEY 1964 and that the extent of cross fertility differs among genotypes of birdsfoot trefoil (MiR! and BUBA 1966, SCHAFF and HIEE 1979). The objectives of this study were to compare self and cross fertility, and to compare SI and PX progeny testing for forage and seed yield within two populations of birdsfoot trefoil. A third objective was to compare the relative performance of the two populations. Materials and MethodsThe cultivar 'Leo' and the progeny from a fourth cycle of recurrent selection in birdsfoot trefoil were used in this investigation. The latter population origin...

Somaclonal variation in Lotus corniculatus L. in relation to plant breeding purposes

“…In polyploid species, like L . corniculatus, inbreeding depression for forage yield is remarkable and it causes the reduction of selfed progeny performance with respect to the polycross one and it may result in lower correlation between the parents and selfed progenies (Onokpise et al ., 1987) .…”

Magnitude of inbreeding depression and genetic variation analysis of agro‐morphological traits in orchardgrass

“…According to Onokpise et al. (), forage and seed yield in S 1 progeny were lower than in polycross progeny in the birdsfoot trefoil, indicating inbreeding depression for these traits (Onokpise et al. ).…”

“…(), forage and seed yield in S 1 progeny were lower than in polycross progeny in the birdsfoot trefoil, indicating inbreeding depression for these traits (Onokpise et al. ). Berdahl and Ray () reported that the S 1 population had lower yields than the OP population in crested wheatgrass.…”

“…A cross‐pollinated population of birdsfoot trefoil was found to have larger pods and more seeds than a selfed population (Onokpise et al. ). It can be attributed to inbreeding due to selfing, as a result of pollen or ovule abortion or a combination of both (Onokpise et al.…”

“…It can be attributed to inbreeding due to selfing, as a result of pollen or ovule abortion or a combination of both (Onokpise et al. ). Polycross progeny had better survival than selfed progeny, and forage and seed yield in the selfed progeny were lower than in the polycross progeny of birdsfoot trefoil, indicating inbreeding depression for both traits (Onokpise et al.…”