Production of Hypo- and Hypertetraploid Seedlings from Open-, Self-, and Cross-Pollinated Hypo- and Hypertetraploid Grape

Abstract

Seedless grape (Vitis spp.) cultivars with large berries can be developed from hypo-and hypertetraploid seedlings. The low occurrence of hypo-and hypertetraploid seedlings, however, has impeded the breeding of new hypo-and hypertetraploid grape varieties. In order to establish hypoand hypertetraploid seedlings, we examined the chromosome numbers in seedlings of self-, open-, and cross-pollinated hypotetraploid 'Takao' and hypertetraploid 'RB9127K' grape. Three of the five seedlings (60%) from 'Takao' were aneuploid, including one with 74 chromosomes (2n=4x-2) and two with 75 chromosomes (2n=4x-1). In 'RB9127K', 26 of the 193 seedlings (13.5%) were aneuploid, including three seedlings with 75 chromosomes (2n=4x-1), 18 with 77 chromosomes (2n=4x+1), and five with 78 chromosomes (2n=4x+2). The high frequency of aneuploids from 'Takao' and 'RB9127K' grape indicates that meiosis in hypo-and hypertetraploid female parents is prone to segregation error. These results suggest that various hypo-or hypertetraploid seedlings can be successfully produced using hypo-or hypertetraploid grapes as female parents, which can contribute to the development of new seedless grape varieties with large berries.

‘Black Star’: An Early-maturing Seedless Grape Cultivar

“…Of them, only 12 seeds germinated. The triploidy status of these individuals was confirmed by counting the chromosome number as described by Park et al (2016). 'Black Star', initially named 'GWT-80', which was identified as a triploid selection with superior growth characteristics during its early growth stages, was multiplied for evaluation of its vine performance and fruit quality in the y Ten clusters from gibberellic acid-treated (100 ppm) vines were sampled randomly from five vines at the optimal harvest period for calculation.…”

In vitro embryo rescue for the production of hypotetraploids after cross between hypotetraploid and tetraploid grape cultivars

“…It was found that cross between hypotetraploid and tetraploid grapes generates hypotetraploids more easily compared to previously used breeding methods. However, low seed germination caused by abortive embryos after cross pollination has remained a problem that hinders the breeding of hypotetraploid grape cultivars (Park et al, 2016). In vitro embryo rescue technique has been successfully applied to generate hybrid seedlings that can hardly be obtained by artificial cross combination of grape cultivars such as stenospermic × stenospermic or tetraploid × diploid grapes (Liu et al, 2016;Jiao et al, 2018).…”

Combined treatment with gibberellic acid and thidiazuron improves fruit quality of ‘Red Dream’ grape cultivar

“…Recently, many efforts have been made to breed new grape cultivars in Korea, and various grape cultivars are being introduced to farmers (Park et al, 2016;Heo and Park, 2017;Roh et al, 2018;Kim et al, 2020;Park et al, 2022). Among them, 'Red Dream', which is a triploid grape registered in 2016, has the advantage of being able to produce large seedless fruits with just one-time treatment of PGR at the full bloom stage (Park et al, 2022).…”