Mutagenic effects of nitrogen protoxide and oryzalin on “41 B” and “Fercal” grapevine rootstocks seedlings

Abstract

In this study, the mutagenic effects of different doses and exposure times of oryzalin and Nitrogen Protoxide (N 2 O) were tested for stimulating polyploid on 41 B and Fercal grapevine rootstocks seedlings. Ploidy changes were examined by morphological, cytological, macroscopic, and microscopic methods. Leaf thickness, chlorophyll contents, stomatal sizes, and chloroplast numbers of polyploid seedlings stimulated with mutagens increased but their stomatal densities decreased. Flow cytometry (FC) analyses were performed on 50 samples selected by morphological and microscopic preliminary determinations. In FC analyses, 1 tetraploid seedling and 4 mixoploid seedlings from Fercal offspring and 1 mixoploid seedling from 41 B offspring were verified. The nuclear DNA content of tetraploid and mixoploid seedlings were increased by 2.00 and 1.34-fold, respectively, when compared to their diploid parents. Chromosome counts in root tip samples propagated in vitro from the tetraploid Fercal offspring confirmed a 2-fold increase compared to the diploid parent. In polyploidy induction studies, it was deemed appropriate to use FC analysis and chromosome count together to confirm the ploidy levels of mutants. Oryzalin and N 2 O applications at different doses and exposure times were found to be effective for inducing polyploidy in 41 B and Fercal grapevine rootstocks.

Polyploidization and genomic selection integration for grapevine breeding: a perspective

“… Kara and Yazar (2021) also examined changes in stomata guard cells but found no differences at the ploidy level. More recently, Kara and Doğan (2023) utilized Oryzalin and N 2 O to treat a total of 1200 plants belonging to two grapevine cultivars, yielding only one tetraploid genotype for each cultivar. These results suggest that in vivo methods for polyploidization in Vitis species are not an effective approach in obtaining high frequency polyploids.…”