The combining ability of selected alfalfa clones as related to the self-fertility of the clones, their F1 and F2 progenies

Abstract

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Sib-compatibility in S1 lines of Medicago sativa L

“…This may be evidenced from the cor relation studies made, which show that self-fertility of the S-^ plants is positively associated with average backcrossand sib-fertility. A positive relationship between self-and cross-fertility has previously been shown by McAllister (1950) and Bolton (1948). Such significant correlations would un likely be brought about by the operation of the S incompatibil ity gene systems.…”

“…Koffman (1959) found that selfed progenies yielded only 55 to 75 per cent of the forage yield of non-inbred parental clones. Similar results were obtained by McAllister (1950). Bolton (1948) showed that progenies of crosses among second generation selfed plants derived from the same parents were intermediate in seed and forage yield between comparable inbred lines and outcross progenies.…”

“…If such is the case, then it would seem that a program of inbreeding would exclude those clones which are low in self-fertility. As previously shown by Wilsie (1951) and McAllister (1950) these may constitute as much as 30 to 1l0 per cent of a non-inbred population.…”

Selfing and selection in alfalfa breeding programmes

“…McALLISTER (1951) found a positive correlation between yields of parental clones and yields of their h and Fl progenies . DAvis (1953), in a wide discussion of the subject, observed that the difference between polycross progenies with the highest and lowest yield was half that observed between the best and the poorest f, progeny .…”

Recurrent Selection for High Self‐Fertility in Vernal Alfalfa (Medicago Sativa L.)

“…Similarly, Wilsie (1958) found self-fertility values of 437 alfalfa hybrids from first-generation single-and 3-way crosses were strongly skewed, Wilsie and Skory (1948) observed a range in selffertility from 0.24 to 2.23 seeds per tripped flower among alfalfa clones, and Wilsie (I95I) reported a range of selffertility from 0.12 to 1.84 seeds per tripped flower. Studies by McAllister (1950), Koffman (1959) and Williams (1964) showed remarkably wide ranges in self-fertility, also. San dal (1946) found 0.15 seeds and 1.25 seeds per flower, re spectively, for low and high-fertility groups of clonal lines.…”