QTL Analysis of Tuber Dormancy and Sprouting in Potato

Combining conventional QTL analysis and whole-exome capture-based bulk-segregant analysis provides new genetic insights into tuber sprout elongation and dormancy release in a diploid potato population

“…In particular, the mapping population used by Freyre et al (1994) is derived from a 'tuberosum hybrid' (female) and 'S. phureja' (male) cross and that deployed by Bisognin et al (2018) contained S. tuberosum and S. phureja in the pedigree suggesting that QTL observed in these studies have higher correspondence and transferability with those observed in the current study.…”

“…Despite the scant marker distribution in the older studies, the QTL reported in the present study appear to be in approximately the same locations as those detected in the earlier two publications, that is towards the 'top' of chromosomes 2 and 3 after accounting for possible reverse genetic orientation for these chromosomes reported by Freyre et al (1994) and towards 'bottom' of chromosomes 4, 5, 8 and 10; locations for chromosome 1 (van den Berg et al 1996) and 7 (Freyre et al 1994) QTL were unresolved or not clear in the reported studies, so it is tantalising to speculate that these effects may share common origins. A much more recent potato dormancy study (Bisognin et al 2018) also reports a complex pattern of genetic effects mapping to seven potato chromosomes (2, 3, 5, 6, 7, 9 and 11). There is a high likelihood that the common QTL effects detected on chromosomes 2, 3, 5, 6 and 7 in the previous publication may be syntenic with effects reported here at similar map positions.…”

QTL mapping for microtuber ABA content in a diploid potato population

“…As the single most important non-cereal crop species, potato (Solanum tuberosum L.) is grown in approximately 150 countries and is an important part of the global food system. The contribution of potatoes in the developing world for nutrition and food security and for the elimination of hunger and malnutrition is equal to that of rice, wheat, and maize but with a higher yield ratio (Shrestha et al 2018) In potato tubers, the dormancy period, also known as the resting period, represents the physiological condition when the tubers are incapable of sprout growth (Bisognin et al 2018); this is true even if conditions are favorable (i.e., darkness, high humidity and warm temperature) for growth (Sonnewald and Sonnewald 2014). A long dormancy period guarantees that the quality of stored tubers can be preserved for up to 7 months after harvest (Tarn et al 1992).…”

Effects of Physical, Mechanical and Hormonal Treatments of Seed-Tubers on Bud Dormancy and Plant Productivity

“…Genetic analysis highlighted that metabolism, synthesis and signaling of phytohormones, such as abscisic acid, and gibberellins, are regulated by QTL (quantitative traits loci) underlying genes, some of which coincided with QTL underlying genes involved in dormancy and tuberization [16,17]. Moreover, recently Bisognin et al [18], reported that at least eight QTLs are involved in the termination of dormancy. Full dormancy release is regulated by both gibberellins and cytokinins [15], dormancy induction is promoted by abscisic acid and ethylene, and abscisic acid is considered to be responsible for dormancy maintenance [19].…”

“…Dormancy termination in seed-tuber by exogenous compounds has several practical purposes such as for export or local use, for handle genetic materials of different end-uses (ware or seed) and for planning the next planting season [22]. In particular, seed-tuber producers have an interest in applying techniques that easily and effectively break dormancy allowing the use of seed-tubers for a new growing cycle just few weeks after harvesting [18,23]. Different protocols have been set up to force the end of dormancy.…”