Potato Species Research Articles

Genome-Wide Identification and Expression Analysis of the ALKB Homolog Gene Family in Potato (Solanum tuberosum L.).

N6-methyladenosine (m6A) is an abundant and pervasive post-transcriptional modification in eukaryotic mRNAs. AlkB homolog (ALKBH) proteins play crucial roles in RNA metabolism and translation, participating in m6A methylation modification to regulate plant development. However, no comprehensive investigations have been conducted on ALKBH in potato. Here, 11 StALKBH family genes were identified in potato and renamed according to BLASTP and phylogenetic analyses following the Arabidopsis genome. The characteristics, sequence structures, motif compositions, phylogenetics, chromosomal locations, synteny, and promoter cis-acting element predictions were analyzed, revealing distinct evolutionary relationships between potato and other species (tomato and Arabidopsis). Homologous proteins were classified into seven groups depending on similar conserved domains, which implies that they possess a potentially comparable function. Moreover, the StALKBHs were ubiquitous, and their expression was examined in the various tissues of a whole potato, in which the StALKBH genes, except for StALKBH2, were most highly expressed in the stolon and flower. Multiple hormone and stress-response elements were found to be located in the promoters of the StALKBH genes. Further qRT-PCR results suggest that they may be significantly upregulated in response to phytohormones and abiotic stress (except for cold), and the expression of most of the StALKBH genes exhibited positively modulated trends. Overall, this study is the first to report a genome-wide assessment of the ALKBH family in potato, providing valuable insights into candidate gene selection and facilitating in-depth functional analyses of ALKBH-mediated m6A methylation mechanisms in potato.

Haplotype-resolved genome and mapping of freezing tolerance in the wild potato Solanum commersonii.

Solanum commersonii (2n = 2x = 24, 1EBN, Endosperm Balance Number), native to the southern regions of Brazil, Uruguay, and northeastern Argentina, is the first wild potato germplasm collected by botanists and exhibits a remarkable array of traits related to disease resistance and stress tolerance. In this study, we present a high-quality haplotype-resolved genome of S. commersonii. The two identified haplotypes demonstrate chromosome sizes of 706.48 and 711.55Mb, respectively, with corresponding chromosome anchoring rates of 94.2 and 96.9%. Additionally, the contig N50 lengths are documented at 50.87 and 45.16Mb. The gene annotation outcomes indicate that the haplotypes encompasses a gene count of 39 799 and 40 078, respectively. The genome contiguity, completeness, and accuracy assessments collectively indicate that the current assembly has produced a high-quality genome of S. commersonii. Evolutionary analysis revealed significant positive selection acting on certain disease resistance genes, stress response genes, and environmentally adaptive genes during the evolutionary process of S. commersonii. These genes may be related to the formation of diverse and superior germplasm resources in the wild potato species S. commersonii. Furthermore, we utilized a hybrid population of S. commersonii and S. verrucosum to conduct the mapping of potato freezing tolerance genes. By combining BSA-seq analysis with traditional QTL mapping, we successfully mapped the potato freezing tolerance genes to a specific region on Chr07, spanning 1.25Mb, with a phenotypic contribution rate of 18.81%. In short, current research provides a haplotype-resolved reference genome of the diploid wild potato species S. commersonii and establishes a foundation for further cloning and unraveling the mechanisms underlying cold tolerance in potatoes.

High β-sitosterol-D-glucoside content in sweet potato varieties and its anti-breast cancer potential through multiple metastasis-associated signals

β-Sitosterol-D-glucoside (β-SDG) is a phytosterol compound whose antitumor activity has been confirmed by previous studies. However, its suppression on breast cancer remains unclear. To that purpose, we isolated β-SDG from sweet potato and investigated the breast-cancer-inhibiting mechanism using proteomic analysis. The sweet potato species S6 with high β-SDG content were chosen form 36 species and β-SDG was isolated by HPLC. Afterwards, an in situ animal model of breast cancer was established, and β-SDG significantly reduced the tumor volume of MCF-7 xenograft mice. Proteomic analysis of tumor tissues revealed that 127 of these proteins were upregulated and 80 were downregulated. Gene ontology and network analysis showed that regulatory proteins were mainly associated with epithelial-mesenchymal transition (EMT), myogenesis, cholesterol homeostasis, oxidative phosphorylation and reactive oxygen pathways, while Vimentin, NDUF, VDAC1, PPP2CA and SNX9 were the most significant 5 node degree genes. Meanwhile, in vitro and in vivo results showed that the protein expression of PPP2CA and Vimentin, which are markers of EMT, were involved in breast cancer cell metastasis and could be reversed by β-SDG. This work highlights β-SDG as a bioactive compound in sweet potato and the potential therapeutic effect of β-SDG for the treatment of breast cancer by inhibiting metastasis.

Fatty acids and chlorogenic acid content in Plectranthus edulis root tubers.

This study quantified the fatty acid profile and total chlorogenic acid content of various Ethiopian cultivars of the Plectranthus edulis tuber, traditionally known as 'Agew Dinich'. Lipid extraction utilized the Folch method and the acid-catalyzed derivatization method to derivatize the fatty acids into fatty acid methyl ester (FAME) were used. Whereas maceration was used to extract chlorogenic acid from the fresh and freeze- dried tuber samples. Analysis revealed a total of thirteen fatty acids in all P. edulis samples, with nine classified as saturated and four as unsaturated. Palmitic acid was the most abundant fatty acid in P. edulis and accounted for 40.57%-50.21% of the total fatty acid content. The second and third most abundant fatty acids in the P. edulis sample were stearic and linoleic acids, which accounted for 8.38%-12.92% and 8.12%-11.28%, respectively. We reported chlorogenic acid for the first time in this potato species and found it to contain a concentration of 211± 4.2-300±24.7 mg/100g of dry weight basis when the determination was made using fresh samples. On the other hand, these samples yielded a chlorogenic acid concentration ranging from 115 ±8.6 mg/100g-175±3.9 mg/100g of freeze-dried powder samples. These findings suggest that P. edulis tubers could represent a significant dietary source of both chlorogenic acid and fatty acids.

Studying the pathogenic Streptomyces strains responsible for causing potato common scab in Iran and assessing the efficacy of native S. fimicarius-ghR and S. rochei-FsG in reducing scab lesion development in both potato and radish hosts in vivo

ABSTRACT Potato common scab an important widespread disease caused by Streptomyces species, usually can diminish the market value of tubers. None of the disease management methods is considered efficient. Non-pathogenic Streptomyces species owing to their source of bioactive compounds can alleviate scab severity and strengthen plant vigour. During our survey, three pathogenic strains with atypical composition of Pathogenicity Island (PAI) marker genes prevented radish seed germination by ≥98% and exhibited coalescing superficial, raised or mild pitted lesions in pot trials. Based on 16S rRNA and rpoB sequencing, Streptomyces sp. (FG1 and AAb) and S. rochei-HGs were identified. Our research findings have led us to identify S. rochei-HGs as a novel scab-causing species of potato. In addition, two beneficial Streptomyces strains obtained from potato rhizosphere and soil, including S. fimicarius-ghR and S. rochei-FsG, inhibited streptomyces sp.-FG1 growth with the inhibition halo ≥30 mm on agar plates, alleviated the lesion severity index and showed the control efficacy of 88.88 ± 6.41% and 83.33 ± 16.94% on potato, respectively under greenhouse conditions. Both of them can produce siderophore, IAA and solubilise phosphate. By measuring the plant growth attributes, the application of ghR and FsG strains in pathogen-infected soil showed enhancement in potato root and shoot length as well as radish compared with the controls. Evaluation of the inhibitory compounds of studied antagonists by chemistry methods is ongoing. The disease suppressiveness of strains and their plant growth induction should also be validated at the field level.

New Frontiers in Potato Breeding: Tinkering with Reproductive Genes and Apomixis.

Potato is the most important non-cereal crop worldwide, and, yet, genetic gains in potato have been traditionally delayed by the crop's biology, mostly the genetic heterozygosity of autotetraploid cultivars and the intricacies of the reproductive system. Novel site-directed genetic modification techniques provide opportunities for designing climate-smart cultivars, but they also pose new possibilities (and challenges) for breeding potato. As potato species show a remarkable reproductive diversity, and their ovules have a propensity to develop apomixis-like phenotypes, tinkering with reproductive genes in potato is opening new frontiers in potato breeding. Developing diploid varieties instead of tetraploid ones has been proposed as an alternative way to fill the gap in genetic gain, that is being achieved by using gene-edited self-compatible genotypes and inbred lines to exploit hybrid seed technology. In a similar way, modulating the formation of unreduced gametes and synthesizing apomixis in diploid or tetraploid potatoes may help to reinforce the transition to a diploid hybrid crop or enhance introgression schemes and fix highly heterozygous genotypes in tetraploid varieties. In any case, the induction of apomixis-like phenotypes will shorten the time and costs of developing new varieties by allowing the multi-generational propagation through true seeds. In this review, we summarize the current knowledge on potato reproductive phenotypes and underlying genes, discuss the advantages and disadvantages of using potato's natural variability to modulate reproductive steps during seed formation, and consider strategies to synthesize apomixis. However, before we can fully modulate the reproductive phenotypes, we need to understand the genetic basis of such diversity. Finally, we visualize an active, central role for genebanks in this endeavor by phenotyping properly genotyped genebank accessions and new introductions to provide scientists and breeders with reliable data and resources for developing innovations to exploit market opportunities.

Genome-Wide Identification and Expression Analysis of the Broad-Complex, Tramtrack, and Bric-à-Brac Domain-Containing Protein Gene Family in Potato

The BTB (broad-complex, tramtrack, and bric-à-brac) domain, also known as the POZ (POX virus and zinc finger) domain, is a conserved protein–protein interaction domain present in various organisms. In this study, we conducted a genome-wide search to identify and characterize BTB genes in Solanum tuberosum. A total of 57 StBTBs were identified and analyzed for their physicochemical properties, chromosomal distribution, gene structure, conserved motifs, phylogenetic relationships, tissue-specific expression patterns, and responses to hormonal and stress treatments. We found that StBTBs were unevenly distributed across potato chromosomes and exhibited diverse gene structures and conserved motifs. Tissue-specific expression analysis revealed differential expression patterns across various potato tissues, implying their roles in plant growth and development. Furthermore, differential expression analysis under hormonal and stress treatments indicated the involvement of StBTBs in abiotic and biotic stress responses and hormone signaling pathways. Protein–protein interaction analysis identified potential interactions with ribosomal proteins, suggesting roles in translational regulation. Additionally, microRNA target site analysis revealed regulatory relationships between StBTBs and miRNAs. Our study provides a comprehensive understanding of the StBTB gene family in potato, laying the groundwork for further functional characterization and manipulation of these genes to improve stress tolerance and agricultural productivity in potato and related plant species.

Genome-wide identification analysis in wild-type Solanum pinnatisectum reveals some genes defending against Phytophthora infestans.

Solanum pinnatisectum exhibits strong resistance to late blight caused by Phytophthora infestans but only an incomplete genome assembly based on short Illumina reads has been published. In this study, we generated the first chromosome-level draft genome for the wild-type potato species S. pinnatisectum in China using Oxford Nanopore technology sequencing and Hi-C technology. The high-quality assembled genome size is 664Mb with a scaffold N50 value of 49.17 Mb, of which 65.87% was occupied by repetitive sequences, and predominant long terminal repeats (42.51% of the entire genome). The genome of S. pinnatisectum was predicted to contain 34,245 genes, of which 99.34% were functionally annotated. Moreover, 303 NBS-coding disease resistance (R) genes were predicted in the S. pinnatisectum genome to investigate the potential mechanisms of resistance to late blight disease. The high-quality chromosome-level reference genome of S. pinnatisectum is expected to provide potential valuable resources for intensively and effectively investigating molecular breeding and genetic research in the future.

Genetic diversity studies between Ipomoea wild species and cultivated sweet potato (Ipomoea batatas (L.) Lam.) using SSR markers

Sweet potato (Ipomoea batatas (L.) Lam) is one of the major tuber crops in Asian countries, including India, yet the interrelationship and genetic variability among the cultivar and its crop wild relatives remain obscure. The wild relatives of sweet potato represent a vital source of untapped genetic diversity in the breeding programs. In this study, a set of 12 Simple Sequence Repeats (SSR) markers were utilized to understand the extent of genetic diversity and relationship within and between 20 sweet potato accessions, 23 wild Ipomoea species and two Merremia species for utilization in breeding programmes. The SSR primers produced 84 polymorphic alleles within the range of 105–393 bp, collectively showing an average polymorphism of 94.5 %. The average Polymorphic Information Content (PIC) value of 0.67 showed that all the primers were polymorphic in nature. Similarity coefficient based dendrogram and Principal Component Analysis (PCA) scatter plot clearly differentiated all the cultivars and wild species. The cluster dendrogram analysis revealed the close relationship of cultivars with I. triloba and I. trifida at a similarity index of 0.75. Our analysis showed a high degree of genetic variability within and between hexaploid sweet potato and diploid wild species, whereas lower within the cultivars, which shows that there is a high level of genetic diversity exists within the Ipomoea species for its utilization in breeding programs. Thus, the two wild species, I. trifida and I. triloba could be used in hybridization for improvement of sweet potato through ploidy manipulation.

Leaf and tuber resistance to <I>Phytophthora infestans</I> and relationship between these traits in wild potato species

Background. Phytophthora infestans (Mont.) de Bary is a well-known serious pathogen that affects a wide range of currently grown potato cultivars. Control of the disease, including the breeding process, is complicated by the fact that leaf resistance to P. infestans is often unrelated to tuber resistance, resulting in the need to identify individual plants with leaf and/or tuber resistance to be used in breeding programs. In view of this, research efforts to identify such sources are quite relevant. The objective was to assess the occurrence of plants with resistance in both organs among different wild species and analyze the relationship between leaf and tuber resistance within them.Material and methods. Assessment of leaf and tuber resistance in 97 accessions belonging to 36 species was carried out under artificial inoculation. Using the data obtained on each individual plant, the connection between leaf and tuber resistance was analyzed by means of the Wilcoxon matched-pairs test and Spearman’s rank-order correlations.Results. The species with more frequent occurrence of plants combining leaf and tuber resistance and the species with the predominance of leaf or tuber resistance were identified. The statistical analysis did not show complete (100%) correlations between leaf and tuber resistance in any of studied species. In some cases, a significant positive or negative correlation between these characters was found. The assessment results for the studied species/accessions can facilitate the search for leaf and/or tuber resistance sources capable of improving potato cultivars susceptible to late blight.

The haplotype-resolved T2T genome assembly of the wild potato species Solanum commersonii provides molecular insights into its freezing tolerance

The haplotype-resolved T2T genome assembly of the wild potato species Solanum commersonii provides molecular insights into its freezing tolerance

The use of <i>in vitro</i> androgenesis for the involvement of interspecific hybrids between <i>Solanum tuberosum</i> L. and wild allotetraploid potato species <i>Solanum stoloniferum</i> Schltdl. et Bouché into breeding

Wild allotetraploid potato species Solanum stoloniferum Schltdl. & Bouché from Mexico is regarded as a valuable source of resistance genes for use in breeding. However, introgression of its resistance genes into breeding material is hampered by a set of reproductive barriers. The genomic difference between S. stoloniferum (genome ААВВ) and S. tuberosum L. (AAAA) is one of them. This makes questionable the possibility of transferring a variety of valuable genes of the wild species localized on the chromosomes of its genome B into the genome of cultivated potatoes. It is proposed to produce tetraploid (4x, AAAB) interspecific hybrids of S. stoloniferum, which are regarded as more promising for homoeological recombination than pentaploid (5x, ААААВ) hybrids commonly used in the introgression schemes. However, the effective ploidy of tetraploid hybrids (3EBN) hinders their backcrossing to cultivated potatoes (4 EBN). For instance, our attempts to involve the tetraploid hybrid of S. stoloniferum IGC16/36.1 obtained by us into hybridization with potato varieties were unsuccessful for a number of years. To solve this problem, we suggested a technique based on the production of 4x plants obtained in anther culture of this hybrid. The present research was aimed at assessing the efficiency of this approach.Thirty-one plants were obtained in anther culture (androgenic clones, androclones) of the hybrid IGC16/36.1 in 2018. Most of them exceeded the initial hybrid in habitus strength and flowering intensity. As a result of crosses made in 2019, 1039 hybrid seeds were obtained from crossing 21 androclones with the ‘Lemhi Russet’ variety (8.7 seeds/pollination), 1017 seeds (7.5 seeds/pollination) from crosses of 23 androclones with the ‘Quarta’ variety, and 716 seeds (12.3 seeds/pollination) from crosses of 11 androclones and a diploid potato line IGC 17n8 capable of producing fertile unreduced (2n) pollen. The hybrid seeds had good germination rate of 70-90%. Among the androclones that gave progeny in crosses with potato varieties, we identified genotypes carrying DNA markers of late blight (LB) resistance genes Rpi-sto1, R2 and R3b, PVY resistance genes Ryadg, Rysto and Rychc, and potato wart disease resistance gene Sen2 (these markers were found in the initial accession of S. stoloniferum PI 205522 and in the IGC 16/36.1 hybrid). Despite the complex nature of inheritance of the analyzed markers in progenies of backcrosses of androclones, a number of isolated hybrids carried several markers, including those of the Rpi-sto1, a broad-spectrum gene for high resistance to late blight. Hybrids with relatively high tuber productivity, features of cultivated potatoes such as regularly shaped tubers with small eyes, and high field resistance to late blight were selected.The prospects for using androclones of the tetraploid interspecific hybrid IGC 16/36.1 for increasing the frequency of homoeologous A/B recombination of chromosomes are discussed.

Characterisation and mapping of a Globodera pallida resistance derived from the wild potato species Solanum spegazzinii

Key messageA new resistance locus acting against the potato cyst nematode Globodera pallida was mapped to chromosome VI in the diploid wild potato species Solanum spegazzinii CPC 7195.The potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis are economically important potato pests in almost all regions where potato is grown. One important management strategy involves deployment through introgression breeding into modern cultivars of new sources of naturally occurring resistance from wild potato species. We describe a new source of resistance to G. pallida from wild potato germplasm. The diploid species Solanum spegazzinii Bitter accession CPC 7195 shows resistance to G. pallida pathotypes Pa1 and Pa2/3. A cross and first backcross of S. spegazzinii with Solanum tuberosum Group Phureja cultivar Mayan Gold were performed, and the level of resistance to G. pallida Pa2/3 was determined in progeny clones. Bulk-segregant analysis (BSA) using generic mapping enrichment sequencing (GenSeq) and genotyping-by-sequencing were performed to identify single-nucleotide polymorphisms (SNPs) that are genetically linked to the resistance, using S. tuberosum Group Phureja clone DM1-3 516 R44 as a reference genome. These SNPs were converted into allele-specific PCR assays, and the resistance was mapped to an interval of roughly 118 kb on chromosome VI. This newly identified resistance, which we call Gpa VIlspg, can be used in future efforts to produce modern cultivars with enhanced and broad-spectrum resistances to the major pests and pathogens of potato.

In silico search for and analysis of R gene variation in primitive cultivated potato species.

Pathogen recognition receptors encoded by R genes play a key role in plant protection. Nowadays, R genes are a basis for breeding many crops, including potato. Many potato R genes have been discovered and found suitable for breeding thanks to the studies of a wide variety of wild potato species. The use of primitive cultivated potato species (PCPS) as representatives of the primary gene pool can also be promising in this respect. PCPS are the closest to the early domesticated forms of potato; therefore, their investigation could help understand the evolution of R genes. The present study was aimed at identifying and analyzing R genes in PCPS listed in the open database of NCBI and Solomics DB. In total, the study involved 27 accessions belonging to three species: Solanum phureja Juz. & Bukasov, S. stenotomum Juz. & Bukasov and S. goniocalyx Juz. & Bukasov Materials for the analysis were the sequencing data for the said three species from the PRJNA394943 and PRJCA006011 projects. An in silico search was carried out for sequences homologous to 26 R genes identified in potato species differing in phylogenetic distance from PCPS, namely nightshade (S. americanum), North- (S. bulbocastanum, S. demissum) and South-American (S. venturii, S. berthaultii) wild potato species, as well as the cultivated potato species S. tuberosum and S. andigenum. Homologs of all investigated protein-coding sequences were discovered in PCPS with a relatively high degree of similarity (85-100 %). Homologs of the Rpi-R3b, Rpi-amr3 and Rpi-ber1 genes have been identified in PCPS for the first time. An analysis of polymorphism of nucleotide and amino acid sequences has been carried out for 15 R genes. The differences in frequencies of substitutions in PCPS have been demonstrated by analysis of R genes, the reference sequences of which have been identified in different species. For all the studied NBS-LRR genes, the proportion of substituted amino acids in the LRR domain exceeds this figure for the NBS domain. The potential prospects of using PCPS as sources of resistance to Verticillium wilt have been shown.

DNA-Binding with One Finger (Dof) Transcription Factor Gene Family Study Reveals Differential Stress-Responsive Transcription Factors in Contrasting Drought Tolerance Potato Species.

DNA-binding with one finger (Dof) proteins comprise a large family that play central roles in stress tolerance by regulating the expression of stress-responsive genes via the DOFCORE element or by interacting with other regulatory proteins. Although the Dof TF has been identified in a variety of species, its systemic analysis in potato (Solanum tuberosum L.) is lacking and its potential role in abiotic stress responses remains unclear. A total of 36 potential Dof genes in potato were examined at the genomic and transcriptomic levels in this work. Five phylogenetic groups can be formed from these 36 Dof proteins. An analysis of cis-acting elements revealed the potential roles of Dofs in potato development, including under numerous abiotic stress conditions. The cycling Dof factors (CDFs) might be the initial step in the abiotic stress response signaling cascade. In potato, five CDFs (StCDF1/StDof19, StCDF2/StDof4, StCDF3/StDof11, StCDF4/StDof24, and StCDF5/StDof15) were identified, which are homologs of Arabidopsis CDFs. The results revealed that these genes were engaged in a variety of abiotic reactions. Moreover, an expression analysis of StDof genes in two potato cultivars ('Long10' (drought tolerant) and 'DXY' (drought susceptible)) of contrasting tolerances under drought stress was carried out. Further, a regulatory network mediated by lncRNA and its target Dofs was established. The present study provides fundamental knowledge for further investigation of the roles of Dofs in the adaptation of potato to drought stress, aiming to provide insights into a viable strategy for crop improvement and stress-resistance breeding.

Morphometric analysis of wild potato leaves

AbstractTo catalog and promote the conservation and use of crop wild relatives, comprehensive phenotypic and genotypic information must be available. Plant genotyping has the power to resolve the phylogenetic relationships between crop wild relatives, quantify genetic diversity, and identify marker-trait associations for expedited molecular breeding. However, access to cost-effective genotyping strategies is often limited in underutilized crops and crop wild relatives. Potato landraces and wild species, distributed throughout Central and South America, exhibit remarkable phenotypic diversity and are an invaluable source of resistance to pests and pathogens. Unfortunately, very limited information is available for these germplasm resources, particularly regarding phenotypic diversity and potential use as trait donors. In this work, more than 150 accessions corresponding to 12 species of wild and cultivated potatoes, collected from different sites across the American continent, were analyzed using computer vision and morphometric methods to evaluate leaf size and shape. In total, more than 1100 leaves and leaflets were processed and analyzed for nine traits related to size, shape, and color. The results produced in this study provided a visual depiction of the extensive variability among potato wild species and enabled a precise quantification of leaf phenotypic differences, including shape, color, area, perimeter, length, width, aspect ratio, convexity, and circularity. We also discussed the application and utility of inexpensive but comprehensive morphometric approaches to catalog and study the diversity of crop wild relatives. Finally, this study provided insights for further experimental research looking into the potential role of leaf size and shape variation in plant–insect interactions, agronomic productivity, and adaptation.

An international breeding project using a wild potato relative Solanum commersonii resulted in two new frost-tolerant native potato cultivars for the Andes and the Altiplano.

This breeding project, initiated at the United States Potato Genebank (USPG) in collaboration with Peruvian partners Instituto Nacional de Innovacion Agraria (INIA), International Potato Center, Peru (CIP), and local farmers, sought to enhance cold hardiness and frost tolerance in native potato cultivars in Peru. The Andes and Altiplano are often affected by frost, which causes significant reduction in yield; creating varieties with superior resilience is a critical undertaking. The goal was to transfer outstanding non-acclimated cold tolerance and acclimation capacity found in wild potato species Solanum commersonii (cmm). Breeding families segregating for cold hardiness were created using (a) a somatic hybrid cmm + haploid Solanum tuberosum (tbr) (cv. Superior, US variety from Wisconsin) as male and (b) seven cultivars native to Peru of the species S. tuberosum sbsp. andigenum (adg) as females. All plant materials were part of the USPG germplasm collection. Sexual seeds of each family were sent to Peru for evaluations under the natural conditions of the Andean highlands and Altiplano. The plants were assessed for their response to frost, and genotypes showing exceptional tolerance were selected. Plants were also evaluated for good tuber traits and yield. Initial planting involving ~2,500 seedlings in five locations resulted in selecting 58 genotypes with exceptional frost tolerance, good recovery capacity after frost, and good tuber traits. Over the years, evaluations continued and were expanded to replicated field trials in the harsher conditions of the Altiplano (Puno). All trials confirmed consistency of frost tolerance over time and location, tuber quality, and yield. After 8 years, two advanced clones were considered for cultivar release because of their exceptional frost tolerance and superior field productivity that outyielded many of the established cultivars in the region. In November 2018, a new native cultivar named Wiñay, a Quechua word meaning "to grow" was released in Peru. In 2022, a second cultivar followed with the name Llapanchispaq (meaning "for all of us"). This project evidenced that a multinational and all-encompassing approach to deploy valuable genetic diversity can work and deliver effective results. This is even more significant when outcomes can promote food security and sustainability in very vulnerable regions of the world.

Screening for Resistance Resources against Bacterial Wilt in Wild Potato.

Potato is an important crop, used not only for food production but also for various industrial applications. With the introduction of the potato as a staple food strategy, the potato industry in China has grown rapidly. However, issues related to bacterial wilt, exacerbated by factors such as seed potato transportation and continuous cropping, have become increasingly severe in the primary potato cultivation regions of China, leading to significant economic losses. The extensive genetic diversity of Ralstonia solanacearum (R. solanacearum), which is the pathogen of bacterial wilt, has led to a lack of highly resistant potato genetic resources. There is a need to identify and cultivate potato varieties with enhanced resistance to reduce the adverse impact of this disease on the industry. We screened 55 accessions of nine different wild potato species against the bacterial wilt pathogen R. solanacearum PO2-1, which was isolated from native potato plants and belongs to phylotype II. Three accessions of two species (ACL24-2, PNT880-3, and PNT204-23) were identified with high resistance phenotypes to the tested strains. We found these accessions also showed high resistance to different phylotype strains. Among them, only PNT880-3 was capable of flowering and possessed viable pollen, and it was diploid. Consistent with the high resistance, decreased growth of R. solanacearum was detected in PNT880-3. All these findings in our study reveal that the wild potato PNT880-3 was a valuable resistance source to bacterial wilt with breeding potential.

Typification of intraspecific taxa in <i>Solanum andigenum</i> Juz. et Buk.

Taxonomic studies were carried out in the collection of cultivated potato species kept in the Herbarium of Cultivated Plants of the World, Their Wild Relatives, and Weeds (WIR). It allowed us to proceed with typifying the names of intraspecific taxa within Solanum andigenum Juz. et Buk., belonging to three geographical groups: Colombian, South Peruvian, and Bolivian. The WIR herbarium collections comprise the taxonomic diversity of cultivated potatoes described by Russian taxonomists and based on the study of plant materials collected in South America during the expeditions organized by N. I. Vavilov in the late 1920s – early 1930s. Verification of protologs and herbarium specimens resulted in locating herbarium sheets that appeared to be syntypes of six varieties and eleven forms. Lectotypes were also designated for the following three forms: S. andigenum f. huaman-uma Buk. et Lech., S. andigenum f. lecke-umo Buk. et Lech., S. andigenum f. pacus Lech.

Wild relatives of potato (Solanum L. sec. Petota) poorly sampled and unprotected in Colombia

AbstractWild potato relatives (Solanum L. sec. Petota) play a vital role in crop improvement, understanding crop evolution, and conserving potato diversity. However, these invaluable resources are often neglected and underutilized and are susceptible to threats such as climate change, urbanization, and agricultural expansion. Little is known about the diversity, conservation status, and distribution of wild potato species in Colombia. To address this gap, we assessed the conservation status of five wild potato relatives conserved in the ex situ Colombian Central Collection. Five species were analyzed for their spatial patterns of biodiversity, conservation status, and conservation gaps. Colombia was found to have six centers of species richness, four areas of endemism, and six biogeographical regions. Of the five native species, only one was classified as adequately conserved for ex situ conservation, while the other four were considered low priority. In contrast, for in situ conservation, three species showed high priority, one was classified as medium priority, and one as low priority. In light of these findings, we propose three conservation strategies: (1) conducting collection missions to increase accessions in the national germplasm bank, prioritizing high‐priority species; (2) identifying and protecting unprotected natural habitats and engaging stakeholders to enhance in situ conservation efforts; and (3) establishing regional community genebanks to ensure localized conservation efforts.