Portal de Periódicos da CAPES

CHROMOSOME NUMBERS IN CHIHUAHUAN DESERT CACTACEAE. TRANS‐PECOS TEXAS

1978; Wiley; Volume: 65; Issue: 5 Linguagem: Inglês

10.1002/j.1537-2197.1978.tb06104.x

1537-2197

James F. Weedin, A. Michael Powell,

Biological Control of Invasive Species

Chromosome numbers are presented for 100 collections of Cactaceae from the Trans‐Pecos region of Texas. A total of 65 taxa representing 52 species and 12 genera were counted, including first reports for 45 taxa and new ploidy levels for four taxa. Notable among those listed are counts for Opuntia schottii var. grahamii ( n = 11, ca. 22), O. stanlyi ( n = 22), O. arenaria ( n = 11), O. phaeacantha var. spinosibacca ( n = 22), O. lindheimeri var. lindheimeri ( n = 11), O. strigil ( n = 11), Echinocereus enneacanthus var. cf. dubius ( n = ca. 22), E. pectinatus var. neomexicanus ( n = 22), and Thelocactus bicolor var. bicolor ( n = 22). Endomitosis was found to be present in O. phaeacantha var. spinosibacca, Mammillaria pottsii , and Neolloydia intertexta var. dasyacantha . Meiotic irregularities were noted in some species belonging to the genera Opuntia and Echinocereus . Phytogeographic considerations are inferred from the chromosomal data for O. polyacantha, O. lindheimeri , and O. ficusindica . A base number of x = 11 in Cactaceae is supported.