Flow cytometric analysis of genome size variation in some Passiflora species

Abstract

Nuclear genome size variation was studied in eight taxa of Passiflora. Nuclear DNA content was estimated by flow cytometry of nuclei stained by propidium iodide. 2C DNA content ranged from 3.16-5.36 pg for diploids and 1.83 pg for tetraploid. Differences in nuclear genome size were observed among Passiflora species (pg): P. suberosa 1.83, P. edulis f. edulis 3.16, P. edulis f. flavicarpa (Brazil) 3.19, P. edulis f. flavicarpa (Mexico) 3.21, P. mucronata 3.40, Passiflora edmundoi 3.43, P. laurifolia 3.88, P. giberti 3.92, P. quadrangularis 5.36, the largest value being up to 192% greater than the smallest. The means of 2C DNA content were compared by the Tukey test, and the differences in genome size permitted the recognition of five taxa groups. The result was the same for the means 2C genome size (Mbp) values. The genetic parameters were studied with their respective estimators, phenotypic variance (sigma2F), genotypic variability (PhiG), and the genotypic determination index (H2). The genotypic determination index presented high magnitude estimates (greater than 99%) emphasizing the reliability of the results and demonstrating the efficiency of determining the DNA content in the species using only one leaf per plant. Passiflora species show great phenotypic variability and have different geographic distribution that might implicate in genetic diversity.

Ploidy stability of somatic embryogenesis-derived Passiflora cincinnata Mast. plants as assessed by flow cytometry

“…The 2C DNA content of some Passiflora species is between 1.83 and 5.86 pg, and the genome size is between 896 and 5,252 Mbp (Souza et al 2004). In this study, the values found for P. cincinnata are close to those found for P. edulis Sims edulis (3.16 pg; 3,096 Mbp, 2n = 2x = 18) and P. edulis f. flavicarpa (3.19 pg; 3,126 Mbp, 2n = 2x = 18), but are 1.78 times lower than those of P. quadrangularis (5.36 pg; 5,252 Mbp, 2n = 2x = 18) and 1.64 times higher than the smallest genome of P. suberosa (1.83 pg; 896 Mbp, 2n = 4x = 24).…”

Organogenesis from root explants of commercial populations of Passiflora edulis Sims and a wild passionfruit species, P. cincinnata Masters

“…The 2C DNA content of some Passiflora species ranged from 1.83 to 5.86 pg and the genome size between 896 and 5,252 Mpb (Souza et al 2004). The 2C DNA content of P. cincinnata (2.99 pg) and P. edulis f. flavicarpa (3.21 pg) confirmed previous results reported by Paim Pinto et al (2010) and Souza et al (2004Souza et al ( , 2008 respectively.…”

Polinização seletiva em maracujazeiro amarelo (Passiflora edulis f. flavicarpa) monitorada por vetores canônicos

“…Apesar da importância, poucos têm sido os estudos de avaliação de grupos heteróticos de maracujazeiro amarelo, visando à indicação de cruzamentos para futuros programas de melhoramento com a cultura. Os estudos até então desenvolvidos têm dado atenção em trabalhos com parâmetros genéticos (VIANA et al, 2004, MORAES et al, 2005, estudos de correlações entre caracteres (VIANA et al, 2003a), estudos com as espécies relacionadas e suas características reprodutivas (MELETTI et al, 2003, VIANA et al, 2003b, SOUZA et al, 2003, 2004a, 2004b, além de estudos sobre diversidade genética em populações (VIANA et. al., 2006).…”