Sunflower in one of the most important oil-crops worldwide. Due to the effects of climate change, it is becoming increasingly important to discover effective and reliable ways to assist it in combating abiotic stresses. A very precise, cost-efficient and reliable way to achieve sunflower abiotic stress resilience, and specifically drought resilience, is through genetic modification. Due to sunflower's recalcitrant nature to transformation and regeneration and strong genotype dependency, it is important to establish a high efficiency regeneration protocol applicable to a wide range of genotypes. The aim of this study was to evaluate the root regeneration capacity of 4 different sunflower genotypes when cultured on 5 different rooting media with the purpose of identifying a combination of sunflower genotype and medium with the highest root regeneration rate. The percentage of rooting of different genotypes showed inter-assay variability (from 0% regeneration to 100% regeneration), however, most consistent root formation was repeatedly observed for genotypes PH-BC2-91 and HA-26-PR. Statistically significant higher root regeneration rates were observed when explants of different genotypes were cultured in MS DV medium compared to four other media used (from around 90% for MS DV to around 50% for the other media). These results further verify the intricate relationship between genotype and medium interactions. The study provides a reliable basis for establishing an efficient sunflower root regeneration protocol and paves the way for the application of biotechnological approaches in breeding and enhancing resilience to abiotic stresses.
Ionas et al. (Thu,) studied this question.