TY - JOUR
AU - Flores, C.
AB - The ploidy levels and amounts of DNA of 23 Opuntia species from Mexico were determined by flow cytometry. Four different ploidy levels (2n = 2x, 2n = 4x, 2n = 6x, 2n = 8x) with 2C-DNA amount ranging from 4.17 pg (Opuntia incarnadilla Griffiths) to 6.53 pg (Opuntia heliabravoana Scheinvar) were determined among the samples analyzed. Polyploidy is widespread (93%) among these Opuntia species. Opuntia heliabravoana Scheinvar was the sole diploid species. Opuntia leucotricha DC. (2C = 5.71 pg), Opuntia spinulifera Salm-Dyck (2C = 5.51 pg), Opuntia robusta Wendl. ex Pfeiff. var. larreyi (F. A. C. Weber) Bravo (2C = 4.98 pg), and Opuntia elizondoana E. Sánchez et Villaseñor (2C = 5.29 pg) were tetraploids. Opuntia oligacantha C.F. Först. (2C = 5.33 pg), Opuntia incarnadilla Griffiths and Opuntia matudae Scheinvar (2C = 5.25 pg) were hexaploids. Opuntia zamundioi Scheinvar (2C = 4.35 pg), Opuntia lasiacantha Pfeiff. (2C =  4.88 pg), Opuntia hyptiacantha F.A.C. Weber (2C = 4.84 pg), Opuntia streptacantha Lem. ssp. streptacantha (2C = 4.64 pg) and Opuntia streptacantha Lem. subsp. aguirrana Scheinvar et A.␣Rodríguez (2C = 4.43 pg), Opuntia megacantha Salm-Dyck (2C = 5.01 pg), Opuntia joconostle F.A.C. Weber. ex Diguet (2C = 4.70 pg), Opuntia ficus-indica (L.) Miller (2C = 4.90 pg), Opuntia albicarpa Scheinvar (2C = 4.80 pg), Opuntia␣amarilla Griffiths (2C = 4.84 pg), Opuntia chavena Griffiths (2C = 4.70 pg), Opuntia cochinera Griffiths (2C = 5.10 pg), Opuntia fuliginosa Griffiths (2C = 4.64 pg), Opuntia pachona Griffiths (2C = 4.70 pg), Opuntia cretochaeta Griffiths (2C = 4.35 pg), Opuntia rzedowskii Scheinvar (2C = 4.77 pg), Opuntia robusta Wendl. ex Pfeiff. ssp. robusta (2C = 4.98 pg) and Opuntia robusta Wendl. ex Pfeiff. var. guerrana (Griffiths) Sánchez-Mejorada (2C = 5.05 pg) were all octoploids. The series Streptacanthae Britton et Rose showed a high level of ploidy with octoploid species except for Opuntia heliabravoanae Scheinvar (2n = 2x), Opuntia elizondoana E. Sánchez and Villaseñor (2n = 4x) and O. matudae Scheinvar (2n = 6x). Opuntia spinulifera Salm-Dyck was determined to be as a tetraploid species. Series Leucotrichae DC. grouped tetraploid and hexaploid species. The monospecific series Heliabravoanae Scheinvar has one species: Opuntia heliabravoana Scheinvar diploid (2n = 2x). The monospecific series Robustae Britton et Rose seems to be a contradictory group; containing three varieties: Opuntia
robusta Wendl. ex Pfeiff. ssp. robusta and Opuntia robusta Wendl. ex Pfeiff. var. guerrana (Griffiths) Sánchez-Mejorada as octoploid taxa and: Opuntia robusta Wendl. ex Pfeiff. var. larreyi (F.A.C. Weber) Bravo which is tetraploid. In earlier report Rafael del Castillo and Mario González-Espinosa (1988) indicate that the arborescent varieties of this species are diploid and the postrate variety tetraploid. Implications for botanical systematics, genetic resources and breeding are discussed.
TI - Genome sizes and ploidy levels in Mexican cactus pear species Opuntia (Tourn.) Mill. series Streptacanthae Britton et Rose, Leucotrichae DC., Heliabravoanae Scheinvar and Robustae Britton et Rose
JF - Genetic Resources and Crop Evolution
DO - 10.1007/s10722-006-9196-z
DA - 2007-02-06
UR - https://www.deepdyve.com/lp/springer-journals/genome-sizes-and-ploidy-levels-in-mexican-cactus-pear-species-opuntia-9j2oXqCHk4
SP - 1033
EP - 1041
VL - 54
IS - 5
DP - DeepDyve
ER -