91) suggested that apogamy and apospory
would probably be associated with changes in chromosome number.
(1998) identified 12 sequence characterized amplified regions (SCARs) cosegregating with apospory in an interspecific population of P.
Rich.) Stapf (2n = 4x = 36) hybrids revealed recombination around the apospory locus (Pessino et al., 1997).
Considering that recombination and flanking markers were found near the apospory locus in both buffelgrass and Brachiaria, it is possible that recombinants near the apomixis locus may only be recovered in intraspecific hybrids.
Associations were found for apospory, which mapped to a single linkage group (7b) in the apomictic parent's map and was absent in the sexual parent's map (Fig.
Thus, polysporic species may have in some cases evolved from diplospory or apospory, as well as monospory.
Ultrastructural characterization of apospory in Panicum maximum.
Genetics of apospory in apomictic Ranunculus auricomus.
The N15-370 marker was of interest in that the parents and the bulks (with one exception) fit the pattern of expression expected for a linked marker, and furthermore because its pattern of expression duplicated that of UGT197-144, which was linked to apospory (Ozias-Akins et al., 1993).
All but marker N15-370 could be shown to be coupled to the apospory gene, and thus on the same chromosome, by estimating linkages for coupling and repulsion phases (Wu et al.
Markers J16-800, UGT1971-44, and M02-680 bracketed the apospory locus and were linked within 5.7 cM (Kosambi) and 10.1 cM (Kosambi) of each other in the Higgins and B-12-9 crosses, respectively (Fig.
Moreover, the lack of aposporous embryo sacs in competition with MMCs, megaspores, or sexual embryo sacs also suggests the absence of apospory