Chromosome number and genome size in Atriplex mollis from southern Tunisia and Atriplex lanfrancoi from Malta (Amaranthaceae)

Abstract

In this work, we investigated the chromosome number and genome size of two Mediterranean Amaranthaceae species, namely Atriplex mollis from southern Tunisia and A. lanfrancoi (formerly Cremnophyton lanfrancoi) from Malta. The two species were found to be diploid (2n = 18) for all examined populations. This result is different from that previously reported for Cremnophyton lanfrancoi Brullo and Pavone (2n = 20). Genome size showed that both species have a close mean amount with 2C = 3.41 and 3.51 pg, respectively. Two groups were distinguished with regard to genome size (P < 0.01). It should, however, be noted that the majority of populations, with the exception of those from Djerba and Chbika, may be intermediate between the two basic groups. Moreover, the difference does not appear to depend on geographical distribution and environmental aspects. It would rather depend on chromosome rearrangements. The morphological similarities, the monophyly of Atriplex including A. lanfrancoi, previously ranked in genus Cremnophyton, sharing the same chromosome number and the same genome size, support the placement of Cremnophyton within the genus Atriplex.

Sympatric genome size variation and hybridization of four oak species as determined by flow cytometry genome size variation and hybridization

“…Natural selection exerts a force on the genome; consequently, GS variation is usually related to the living environment, including the altitude, latitude, temperature, and precipitation level (Bennett et al., 2000; Hidalgo et al., 2015; Knight & Ackerly, 2002; Knight et al., 2005; Li et al., 2017; Zhang et al., 2019). GS allows the detection of interspecific hybrids and/or backcrosses (Vit et al, 2014; Yan et al., 2016) and has been widely applied to various plants, such as Sarcococca (Denaeghel et al., 2017; Prancl et al., 2014; Tlili et al., 2020).…”

Genome Size and Chromosome Number Evolution in Korean Iris L. Species (Iridaceae Juss.)

“…Variation of chromosome numbers, ploidy levels, and genome sizes have been frequently analyzed for a better understanding of evolutionary patterns and species relationships in plants [4][5][6][7]. The genome size values, in combination with data on chromosome numbers, allow ploidy levels to be inferred and can also provide insights into evolutionary relationships between closely related taxa in wild plant groups [7][8][9][10][11][12]. While the monocots are known to have the widest range of genome sizes (0.2-152.2 pg/1 C) among angiosperms [13][14][15], the known genome sizes in the family Iridaceae range from 0.5 pg/1 C in Hesperantha and Sisyrinchium species to 31.4 pg/1 C in Moraea taxa [15,16].…”

“…Among monocots, Iris is an excellent system in which to study the evolutionary patterns of chromosome number and genome size evolution because this group has an exceptionally high diversity of chromosome numbers (n = 7, 8, 9, 10, 11,12,13,15,16,17,18,19,20,21,22,24,25,27,36,54) [17] and genome sizes (1.05-28.2 pg/1 C) [15]. The genus Iris L. is perennial and comprises approximately 300 species worldwide, with the greatest number of endemic species occurring in the Mediterranean and Asia [18][19][20][21].…”