ISSN:
1573-6849
Keywords:
aneuploidy
;
DNA content
;
inversion
;
translocation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Haplopappus gracilis (n=2),Haplopappus revenil (n=4), andHaplopappus wigginsii (n=4) are isolated by F1 hybrid sterility due mainly to translocation heterozygosity. There is no evidence that this can be overcome at the diploid level so that introgression can occur among them. They are also separated geographically, but occasional populations ofH. gracilis andH. ravenil may be brought together along roadways to form sterile hybrids. There were no statistically significant differences in nuclear DNA content among the same or structurally different aneuploidn=2 andn=3 chromosome races or ecotypes ofH. gracilis. Some of theH. gracilis races were not significantly different from one race of the ancestralH. ravenii, and these samples of both species were from plants growing on poor soils in contrast to accessions from normal habitats. How much and which classes of DNA in these species are subject to changes induced by environmental effects is not known. There were no correlations between DNA amounts and altitude, latitude, and longitude.H. wigginsii had a greater amount of DNA per nucleus than eitherH. ravenii orH. gracilis, and its increased DNA content may reflect a more rapid accumulation of noncoding sequences due to facultative self-compatibility not found in the other two species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00710607
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