Visiting Potato from a Breeding Perspective: Accomplishments and Prospects

Several enhancements to the conventional potato breeding are possible though they have encouragement as well as limitations. I n this direction, the marker-assisted selection may be utilized to stack major genes as well as QTLs. Whereas the genetic transformation and genome editing methods accelerate the process of ricking of genes/transgenes. Moreover, these methodologies supplemented with the next-generation sequencing (NGS) platforms and pipelines further aid in reaching the potato ideotype. Here, we overviewed the critical topics that are related to potatoes, from general background, breeding behavior, breeding approaches employed to the potato improvement. Overall, this information complied might serve as background information that is important for potato breeders.

Genetic Diversity and Population Structure of Potato Germplasm in RDA-Genebank: Utilization for Breeding and Conservation

Potato (Solanum tuberosum L.) is an important staple food and economic crop in many countries. It is of critical importance to understand the genetic diversity and population structure for effective collection, conservation, and utilization of potato germplasm. Thus, the objective of the present study was to investigate the genetic diversity and population structure of potato germplasm conserved in the National Agrobiodiversity Center (NAC) of South Korea to provide basic data for future preservation and breeding of potato genetic resources. A total of 24 simple sequence repeat (SSR) markers were used to assess the genetic diversity and population structure of 482 potato accessions. A total of 257 alleles were detected, with an average of 10.71 alleles per locus. Analysis of molecular variance showed that 97% of allelic diversity was attributed to individual accessions within the population, while only 3% was distributed among populations. Results of genetic structure analysis based on STRUCTURE and discriminant analysis of principal components revealed that 482 potato accessions could be divided into two main subpopulations. Accessions of subpopulation 1 mainly belonged to cultivars and breeding lines. Accessions of subpopulations 2 basically corresponded to wild relatives of potatoes. Results of this study provide useful information for potato improvement and conservation programs, although further studies are needed for a more accurate evaluation of genetic diversity and phenotypic traits of potatoes.

Evaluation of the effectiveness of potato improvement in in vitro culture on optimized nutrient media

Studies have been conducted on the use of an optimized Murashige-Scoog nutrient medium to obtain healthy seeds of promising potato varieties. It was found that the use of agarized modified Murashige-Scoog nutrient medium with the addition of exometabolites of fungi of the genus Trichoderma lixii 1.5 mg/l with antimicrobial properties and the antiviral drug “Cycloferon” in a concentration of 0.01% contributes to an increase in the number of virus-free potato regenerants when the method of apical meristems and in vitro improvement is used together. The effectiveness of using the modified medium is confirmed by the following criteria: active growth of test tube potato micro-plants, which is expressed in optimal morphometric indicators on the example of the potato variety “Rosara”; the size of the isolated meristems is 10 mm, which contributes to the output of healthy plants; the survival rate of regenerating plants. It is shown that when using the modified medium, an average of 35-50% of regenerating plants were obtained, depending on the potato variety, free from M, S viruses.

Genomic Analysis of the SUMO-Conjugating Enzyme and Genes under Abiotic Stress in Potato (Solanum tuberosum L.)

SUMO-conjugating enzymes (SCE) and SUMO (Small Ubiquitin-Like Modifiers) genes are important components of SUMOylation. SCE has a crucial role during the SUMOylation process which acts as a catalyst to transfer SUMO to the target protein. Comprehensive studies on SCE and SUMO have been performed in some plants, but studies on these genes remain limited in potato. This study is aimed at exploring the role of StSCE and StSUMO genes in abiotic stress conditions. Nine and seven putative StSCEs and StSUMO genes, respectively, were identified using different methods and databases available for potato. Chromosomal localization showed that SCE and StSUMO genes are unevenly distributed on 7 different chromosomes. Potato genome database was accessed for the expression profile of StSCE and StSUMO genes, and these genes were differentially expressed in different tissues and organs during different phases of plant growth. The expression patterns on different treatments were further evaluated using qRT-PCR for all the StSCE and StSUMO genes. The expression was upregulated in StSCE1/5/6 and 7 under salt and PEG treatment. StSUMO 1/2 and 4 were upregulated under salt stress whereas StSCE9 and StSUMO2 and 4 were observed downregulated under PEG treatment. The results of this study could be useful to explore the role of StSCE genes in potato improvement.

Fine Screening for Resistance to Cold-Induced Sweetening in Potato Hybrids ContainingSolanum raphanifoliumGermplasm

Potato is an indispensable part of human food. Many wild and cultivated potato relatives have been screened to find the best germplasm to improve productivity and quality, but only a small sample of the available biodiversity has been exploited. Most wild relatives are self-incompatible diploids. Genetic variability exists within and among populations, even within a species. Therefore, it is necessary to carry out fine screening to identify individuals carrying traits of interest. This study was carried out to quantify phenotypic variability for resistance to cold-induced sweetening, an important processing trait. Five families were evaluated for potato chip (crisp) color following cold storage of tubers harvested from four greenhouse trials and one field trial. The families were generated by crossing a single diploid clone to five plants from one accession of the wild potato relativeSolanum raphanifolium. Analysis of variance revealed that resistance against cold-induced sweetening was dependent on family and trial. This study underscores the importance of fine screening to select individuals in potato accessions for use in potato improvement.