Cytogenetic characterization of Tropaeolum pentaphyllum Lam

Abstract

The species Tropaeolum pentaphyllum Lam. (batata-crem or crem) is of great economic and medicinal importance. For being an endangered species, the knowledge of its genetic variability is necessary. Considering the lack of cytological studies on this species, this work describes the chromosome numbers, the meiotic behavior, the meiotic index, and the viability of the pollen grains of three populations of T. pentaphyllum from Rio Grande do Sul, Brazil. The three populations presented 2n = 28 chromosomes. Meiotic behavior was regular, with low abnormality frequency (<1%), which culminated in IMx> 90% in the three accessions. This meiotic stability resulted in high production of viable pollen grains, which will favor the use of these accessions in selection programs for commercial purposes, conservation and sustainable use.

Morphological and cytogenetic characterization of new ornamental Passiflora hybrids (P. ‘Vivis’ and P. ‘Jhovi’)

“…Therefore, the F 1 hybrid progeny had high pollen viability, because >70% is considered a high value (Moreira and Gurgel 1940). High pollen viability was found in P. subrotunda, species of ornamental value (Souza et al 2018), and in other species (Tolomeotti et al 2018, Tedesco et al 2019, Krycki et al 2020, including tetraploid plants (Krycki et al 2016). Normal meiotic behavior has been reported in interspecific F 1 hybrids obtained from a cross between P. sublanceolata and P. foetida var.…”

Tuber production of Tropaeolum pentaphyllum Lam. from different sizes of seed-tubers in two cultivation cycles

“…In addition, the fact that the species does not complete its reproductive cycle may limit its geographic occurrence (Rogalski et al, 2022). Thus, in Brazil, due to the low rate of fruit ripening and seed germination (Rogalski et al, 2021), vegetative propagation by tubers (Kinupp & Lorenzi, 2014;Tolomeotti, Felippi, & Donazzolo, 2018;Balestrin et al, 2021;Rogalski et al, 2021;Rogalski et al, 2022a) and stem cuttings (Balestrin et al, 2021) are significant for species conservation.…”

“…Advances are needed regarding its cultivation to domesticate the species and prevent its predatory extraction, which threatens the species' conservation (Rix, 2010). So, it will be possible to exploit crem for commercial purposes, conservation, and sustainable use (Tolomeotti et al, 2018).…”

“…These actions can contribute to conserving the species on the rural property, reducing the pressure to collect tubercles in situ. In the context of family farming, the production of T. pentaphyllum tubers can contribute to people's nutrition and health due to their nutritional potential (Côrrea, 1984;Mors et al, 2000;Trojan-Rodrigues, Alves, Soares, & Ritter, 2012;Braga, Vieira, & Barros, 2018;Tolomeotti et al, 2018). In addition, the sale of surplus production, in natura or processed, enables income generation as a complementary productive activity in the agricultural year.…”

Cytogenetic characterization of Angelonia integerrima Sprengel, a native species with ornamental potential

“…In addition, it is emphasized that several authors, such as Krycki et al (2016), Costa et al (2018), Fachinetto et al (2018), Tolomeotti et al (2018) and Silva et al (2018), have carried out studies involving native species of economic importance, such as the present study.…”