@article {129,
	title = {Biosystematic studies on the genus Isoetes (Isoetaceae) in Japan. II. Meiotic behavior and reproductive mode of each cytotype},
	journal = {American Journal of Botany},
	volume = {83},
	year = {1996},
	note = {Cited By (since 1996):13Export Date: 11 November 2013Source: Scopus},
	month = {1996///},
	pages = {1309 - 1322},
	abstract = {Meiotic behaviors and reproductive modes of Japanese Isoetes were studied. The hexaploid (2n = 66) and the octaploid (2n = 88) of I. japonica consistently formed 33 and 44 bivalents, respectively, at diakinesis and/or metaphase I in both micro- and megaspore mother cells. The tetraploid (2n = 44) of I. sinensis formed 22 bivalents and its hexaploid made 33 bivalents in both types of spore mother cells. At diakinesis and/or metaphase I of microspore mother cells in I. asiatica with 2n = 22, 11 bivalents were detected. Because behaviors of meiosis in all cytotypes mentioned above were quite regular and plants yielded normal-appearing spores, they should reproduce sexually. Aneuploids of I. japonica with 2n = 87 formed 43 bivalents and one univalent, and I. sinensis with 2n = 65 formed 32 bivalents and one univalent in microspore mother cells. Meiosis of both cytotypes was almost regular and yielded microspores of normal appearance. In the heptaploid (2n = 77) of I. japonica, a configuration of 22 bivalents and 33 univalents was detected in micro- and megaspore mother cells, and various irregularities were observed throughout the meiotic divisions. Therefore, the genomic formula of the heptaploid is symbolized as AABBCDE, and the heptaploid is a sterile F 1 hybrid between the hexaploid (AABBCC) and the octaploid (AABBDDEE) of I. japonica. Since diploid and even-numbered polyploids regularly formed bivalents and odd-numbered ones displayed irregularities, allopolyploidy should act as a significant speciation mechanism in this genus.},
	keywords = {Chromosome, Hybrid, Isoetes, megasporogenesis, meiosis, microsporogene sis, polyplo id, reproductive mode},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-0030475989\&partnerID=40\&md5=996182a1723b75d447e3a2137006f7bd},
	author = {Takamiya, M. and Watanabe, M. and Ono, K.}
}
@article {84,
	title = {Revealing unknown or extinct lineages within Iso{\"e}tes (Iso{\"e}taceae) using DNA sequences from hybrids},
	journal = {American Journal of Botany},
	volume = {91},
	year = {2004},
	note = {Cited By (since 1996):25Export Date: 11 November 2013Source: Scopus},
	month = {2004///},
	pages = {899 - 904},
	abstract = {Iso{\"e}tes, a heterosporous lycopod with a fossil record dating back to the Paleozoic, has numerous putative allopolyploids (resulting from hybridization events coupled with doubling of chromosome number). By using the highly variable nucleotide sequences from the second intron of a LFY homologue in Iso{\"e}tes, species could be delimited and hybrid origins determined. The data suggest that reticulate evolution is both common and complex within a more derived species complex of Iso{\"e}tes. Sequences of identifiable parentage and sequences that are unlike any diploid species known were recovered, leading to the conclusion that one or both of the putative parents have not yet been discovered or are extinct. A range of observations concerning allopolyploid speciation were categorized as follows: (1) verification of previous hypotheses regarding parentage (e.g., I. riparia, I. appalachiana), (2) determination that two morphologically distinct allotetraploid species can share the same parentage (I. azorica and I. acadiensis), (3) recognition of a cryptic allotetraploid species, indicated by the presence of different parental genomes (I. "appalachiana" from Florida), and (4) identification of allotetraploid species with one or two unknown parents (e.g., I. tuckermanii, I. acadiensis, I. azorica, and I. hyemalis). Some sequences from diploid species are remarkably uniform among populations (e.g., I. echinospora from various locations in North America, Iceland, and Wales), while others are variable at the subspecies level (e.g., northern and southern populations within I. engelmannii).},
	keywords = {Allopolyploidy, Hybrid origins, Isoetes, LEAFY intron},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-11444256350\&partnerID=40\&md5=420a4ad06820ce82f60d7a70e7db9dec},
	author = {Hoot, S.B. and Napier, N.S. and Taylor, W.C.}
}
