Structure of the incompatibility gene

Lewis, D.

doi:10.1038/hdy.1949.25

Cited by 148 publications

(66 citation statements)

References 13 publications

(2 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For this explanation to hold, we should also have to suppose that the mutation rate from one functional allele to another was so low that there had been insufficient time since the species first appeared in Britain for many, if any, new alleles to have occurred. While estimates of the mutation rate of this locus suggest that this is not high (Emerson, 1939;Lewis, 1948Lewis, , 1951, poppies are known to have been present in the British Isles for at least 3000 years because seed remains have been found in a Bronze Age settlement in Wiltshire (Robinson, 1989). The species may not, of course, always have been as abundant as it is at present.…”

Section: Discussionmentioning

confidence: 99%

The population genetics of the self-incompatibility polymorphism in Papaver rhoeas. VI. Estimation of the overlap between the allelelic complements of a pair of populations

1993

View full text Add to dashboard Cite

The data obtained by cross-classifying the self-incompatibility (S -) alleles of samples taken at random from three natural populations of Papaver rhoeas, presented in the previous paper (Lawrence et al., 1993), are used here to estimate the extent of the overlap between the complements of alleles that pairs of these populations contain. These estimates indicate that this overlap is very great, so that these populations appear to contain essentially the same set of S-alleles. Three possible explanations of these results, which are not expected on the theory of the self-incompatibility polymorphism possessed by this species, are proposed and discussed. It is argued that the most likely of these alternative explanations is that the number of S-alleles in the species is not very much greater than the number of S-alleles that these natural populations contain, a hypothesis which is put to the test in the following paper.

show abstract

Section: Discussionmentioning

confidence: 99%

The population genetics of the self-incompatibility polymorphism in Papaver rhoeas. VI. Estimation of the overlap between the allelelic complements of a pair of populations

1993

View full text Add to dashboard Cite

show abstract

“…than that in other species, in which it appears to be very low (Lewis, 1948(Lewis, , 1949(Lewis, , 1951Hayman & Richter, 1992). The third possibility, which arises from discussion of the second, is that clover populations are highly subdivided, rather than panmictic.…”

mentioning

confidence: 85%

Number of incompatibility alleles in clover and other species

Lawrence

1996

Heredity

View full text Add to dashboard Cite

Atwood's (1942, 1944) data on Tnfolium repens, those of Williams & Williams (1947) on T pratense and those of Williams (1951) on T hybridum have been re-analysed to provide maximum likelihood estimates of the number of incompatibility alleles in the populations or breeders' stocks from which the samples investigated were obtained. These new estimates suggest that populations of T repens contain about 100 alleles and those of T pratense contain up to twice this number. The single estimate from T hybridum, however, suggests that the species in North America possesses only 17 S-alleles. The estimates from clover populations are compared with those from the nine most thoroughly investigated species of other selfincompatible flowering plants and confirm the long-held belief that populations of T repens and T pratense contain more S-alleles than those of the latter. It is argued that the most likely explanation of the large number of S-alleles that natural populations of these species appear to contain is that they are substructured into a large number of semi-isolated neighbourhoods.

show abstract

“…In this species, the style is not partitioned so pollen tubes from all four lobes of the stigma can mix in the style and fertilize ovules in any of the four locules (personal observation). Each anther contains 2000-2500 pollen grains (Lewis, 1948), so pollen was provided in vast excess of that needed to fertilize the 250-300 ovules. The pollinations were paired on the same recipient plant, so that on a given day two identical crosses were performed, one to assess the success of fertilization and the other that of seed maturation.…”

Section: Transformationsmentioning

confidence: 99%

Differential seed maturation uncouples fertilization and siring success in Oenothera organensis (Onagraceae)

Havens

Delph

1996

Heredity

View full text Add to dashboard Cite

This study examines ovule fertilization and seed maturation success in an evening primrose, Oenothera organensis, using transgenic plants. The reproductive success of several pollen donors was compared using individuals transformed with the GUS (/3-glucuronidase) marker gene which allowed the genotype of developing ovules to be determined prior to seed abortion. This marker gene allowed us to discriminate between a pollen donor's success in fertilizing ovules and its success in siring seeds. Transformed plants had decreased microgametophytic vigour, as evidenced by lower than expected fertilization success in vivo and slower pollen tube growth rates in vitro. However, transformation had no apparent effect on offspring sporophytic vigour, including seed mass, seedling emergence and dry weight. This illustrates the effectiveness of fertilization competition in screening out poorly functioning haploid genomes as suggested by Mulcahy (1979). We found significant differences between the percentage of ovules fertilized and the percentage of seeds sired by a pollen donor in four of eight cases. Hence, fertilization success does not always predict seed paternity. The proportion of seeds sired by the transformed donor with very low fertilization success increased, whereas the proportion sired by the donor with relatively high fertilization success was reduced. This resulted in nearly equal siring ability for the two donors in spite of their difference in fertilization ability.

show abstract

Structure of the incompatibility gene

Cited by 148 publications

References 13 publications

The population genetics of the self-incompatibility polymorphism in Papaver rhoeas. VI. Estimation of the overlap between the allelelic complements of a pair of populations

The population genetics of the self-incompatibility polymorphism in Papaver rhoeas. VI. Estimation of the overlap between the allelelic complements of a pair of populations

Number of incompatibility alleles in clover and other species

Differential seed maturation uncouples fertilization and siring success in Oenothera organensis (Onagraceae)

Contact Info

Product

Resources

About