This perspective addresses two of humanity's greatest challenges: feeding a growing population and conserving biodiversity. We begin by examining the legacy of Nikolai Vavilov, who pioneered the improvement of crops such as wheat and beans by hybridizing them with their wild relatives. This strategy used wild species biodiversity to introduce new genetic variation into crops, making them more resilient and productive. Its adoption around the world greatly increased food security and brought lasting benefits to humanity. However, since the 1990 s, well-intentioned laws shifted the governance of biodiversity from a shared global resource to the sovereign control of nation states, with serious unintended consequences. These changes have disrupted the collection, preservation, exchange, and use of biodiversity, all of which are central to Vavilov's strategy for crop improvement and to biodiversity science more broadly. Efforts at reform have been frustrated as the issues became moralized, inhibiting the open dialogue needed for change. Using foundational concepts shared by science and good governance, we propose seven empirically grounded principles for reform, to help realign biodiversity governance with its intended aims. We then illustrate one possible framework-underpinned by global financing to protect biodiversity hotspots-that would align incentives and work in synergy with the principles to foster practical reform. The principles, together with frameworks that align incentives, would create the conditions for stronger biodiversity conservation and research, agricultural development, global food security, and all the associated benefits to humanity.

Drought is a major environmental constraint limiting global peanut productivity. Wild peanut species, characterized by greater genetic diversity, represent valuable resources for improving drought resilience in cultivated peanut. However, the molecular mechanisms underpinning drought tolerance in wild peanut species remain largely unexplored. This study evaluated the drought tolerance of three wild-type peanut accessions from two different species, Arachis dardani GK12946, Arachis dardani V7215, and Arachis ipaënsis K30076. Physiological measurements such as fresh weight and dry weight revealed statistically non-significant differences between drought-stressed and well-watered conditions, indicating strong inherent drought tolerance. Transcriptome analysis revealed that 3272, 3648, and 1181 genes in leaf samples of A. dardani GK12946, A. dardani V7215, and A. ipaënsis K30076 were differentially expressed, respectively. In root samples, 3014, 3472, and 2033 genes were differentially expressed in the same accessions. Notably, differentially expressed genes (DEGs) and set intersection (Venn) analysis suggests A. dardani V7215 exhibited the highest number of DEGs (1155) uniquely expressed in leaves, and 899 DEGs uniquely expressed in roots, suggesting accession-specific gene expression. Gene Ontology enrichment revealed that upregulated genes were associated with abiotic stress responses, temperature stimulus, heat stress, and DNA-binding transcription factor activity. Co-expression network analysis using WGCNA identified key drought-responsive modules, enriched for GO terms like stress regulation, protein folding, as well as GST family amino acid metabolic processes. Overall, this study provides comprehensive insights into the molecular basis of drought tolerance in wild peanut accessions. Our findings establish a valuable resource for functional genomics and crop improvement under water-limited conditions.

Premise: Wild species are strategic sources of valuable traits to be introduced into crops through hybridization. For peanut, the 33 currently described wild species in the section Arachis are particularly important because of their sexual compatibility with the domesticated species, Arachis hypogaea. Although numerous wild accessions are carefully preserved in seed banks, their morphological similarities pose challenges to routine classification. Methods: Using a high-density array, we genotyped 272 accessions encompassing all diploid species in section Arachis. Detailed relationships between accessions and species were revealed through phylogenetic analyses and interpreted using the expertise of germplasm collectors and curators. Results: Two main groups were identified: one with A genome species and the other with B, D, F, G, and K genomes. Species groupings generally showed clear boundaries. Structure within groups was informative, for instance, revealing the history of the proto-domesticate A. stenosperma. However, some groupings suggested multiple sibling species. Others were polyphyletic, indicating the need for taxonomic revision. Annual species were better defined than perennial ones, revealing limitations in applying classical and phylogenetic species concepts to the genus. We suggest new species assignments for several accessions. Conclusions: Curated by germplasm collectors and curators, this analysis of species relationships lays the foundation for future species descriptions, classification of unknown accessions, and germplasm use for peanut improvement. It supports the conservation and curation of current germplasm, both critical tasks considering the threats to the genus posed by habitat loss and the current restrictions on new collections and germplasm transfer.

The identification of informative molecular markers is useful for linkage mapping and can benefit genome-wide association studies by providing fine-scale information about sequence variations. However, high-throughput genotyping approaches are not cost-effective for labs that require frequent use, such as breeding programs that need to perform genotyping on large populations with hundreds of individuals. The number of single nucleotide polymorphism markers generated by those approaches can be far more than needed for most breeding programs; instead, breeders focus on the use of at most hundreds of polymorphic molecular markers for analysis. To help make use of molecular markers a routine tool for breeding programs, we aim to develop a cost-effective genotyping system by using the Tecan Allegro Targeted Resequencing V2 kit. This provides a customized probe design, which indicates that all the DNA fragments synthesized are known targets. SNPs obtained from previous peanut next-generation sequencing data were pre-filtered and selected as targets. These SNP targets were polymorphic among different tetraploid accessions and were selected to be distinguishable from paralogs. A total of 5154 probes were designed to detect 2770 SNP targets and were tested on 48 accessions, which include some closely related sister lines from a breeding population. The results indicated that genotyping by a targeted resequencing approach reduced the cost from around USD 28 (SNP chip and GBS) to USD 18 per sample, while providing polymorphic markers with accurate SNP calls. With this cost-effective genotyping platform, pre-selected SNP markers can be used effectively and routinely for more breeding programs.

'Tamrun OL18L' (Reg. no. CV-155, PI 703068) and 'Tamrun OL19' (Reg. no. CV-156, PI 703069) are high-yielding, high oleic, early-maturing runner-type peanut (Arachis hypogaea L. subsp. hypogaea) cultivars. Tamrun OL18L was derived from a cross between a high oleic runner cultivar, 'Tamrun OL02', and TxL017746, an early runner breeding line selection developed from a cross between PI 109839 and 'Florunner'. Tamrun OL19 was derived from a cross between a high oleic runner cultivar, 'Tamrun OL01', and TxL017746. Maturity of Tamrun OL18L was similar to 'Tamrun OL12', approximately 2 weeks earlier than 'Tamrun OL07'. Tamrun OL19 matured approximately 1 week earlier than Tamrun OL07 and 1 week later than Tamrun OL12. Grades of Tamrun OL18L and Tamrun OL19 were similar, intermediate numerically between but not statistically different from Tamrun OL07 and Tamrun OL12; by comparison, Tamrun OL12 had a significantly lower grade than Tamrun OL07. Grades of Tamrun OL18L and Tamrun OL19 were lower than 'Tamrun OL11' but were similar to 'Georgia-09B', 'FloRun 107,' and 'TUFRunner 511.' Yields were similar to Georgia-09B, FloRun 107, and TUFRunner 511 but were higher than 'Tamnut OL06' and Tamrun OL11. Tamrun OL18L had a larger seed than most cultivars tested, significantly larger than Tamrun OL12 and Tamnut OL06, but was similar in size to Tamrun OL07 and 'Webb'. No differences in flavor were noted between Tamrun OL18L, Tamrun OL19, and check cultivars. Tamrun OL18L and Tamrun OL19 are new high oleic runner peanut cultivars.Tamrun OL18L and Tamrun OL19 mature 1 to 2 weeks earlier than other runners.Earliness and high oleic oil are expected to give reduced chance for off-flavors.Both Tamrun OL18L and Tamrun OL19 have high yield and grades comparable to other cultivars.

Peanut ( Arachis hypogaea L.) is an important crop grown around the world but lacks genetic resistance to many biotic and abiotic stresses. However, these traits can be found in the wild and exotic germplasm to which peanut is genetically related. The genus Arachis contains 83 described species, some of which are home to a reservoir of useful traits and that have served as a source of resistance with their movement into the cultivated peanut. There are several excellent examples of using exotic and wild germplasm to successfully to incorporate biotic resistance traits into cultivated peanut. It is also possible that some of the genetic resources could someday be used to further enhance peanut in unforeseen ways. In this article we present some examples of successful introgression and how these success stories have been achieved.

Arachis hypogaea L. originated in South America and has been taken to most of the tropical and sub-tropical parts of the world as a valuable food crop with high protein content and a source of high energy unsaturated oil. The origin of the cultivated peanut, 2n = 4x = 40, has been the subject of many discussions, but the primitive parents have been agreed on by most as A. duranensis being the A genome donor and A. ipaënsis the B donor; both diploids with 2n = 20. Whether the chromosome doubling of this hybrid occurred in a natural setting or in the garden of a hunter-gatherer-cultivator is also a subject of debate, but most likely it occurred innature. Molecular analyses have established that A. duranensis was the female of the cross.Until recently no one had been successful in making and establishing plants of the cross in that direction. However, the reciprocal cross is easily accomplished and has been reported several times. The primary objective of this paper is to report the successful cross and development of hybrid plants, amphidiploids and populations from the hybrid, A. duranensis × A. ipaënsis.

Identification of peanut cultivars for distinct phenotypic or genotypic traits whether using visual characterization or laboratory analysis requires substantial expertise, time, and resources. A less subjective and more precise method is needed for identification of peanut germplasm throughout the value chain. In this proof-of-principle study, the accuracy of Raman spectroscopy (RS), a non-invasive, non-destructive technique, in peanut phenotyping and identification is explored. We show that RS can be used for highly accurate peanut phenotyping via surface scans of peanut leaves and the resulting chemometric analysis: On average 94% accuracy in identification of peanut cultivars and breeding lines was achieved. Our results also suggest that RS can be used for highly accurate determination of nematode resistance and susceptibility of those breeding lines and cultivars. Specifically, nematode-resistant peanut cultivars can be identified with 92% accuracy, whereas susceptible breeding lines were identified with 81% accuracy. Finally, RS revealed substantial differences in biochemical composition between resistant and susceptible peanut cultivars. We found that resistant cultivars exhibit substantially higher carotenoid content compared to the susceptible breeding lines. The results of this study show that RS can be used for quick, accurate, and non-invasive identification of genotype, nematode resistance, and nutrient content. Armed with this knowledge, the peanut industry can utilize Raman spectroscopy for expedited breeding to increase yields, nutrition, and maintaining purity levels of cultivars following release.

Great efforts have been done to collect germplasm of the Arachis genus in South America, however, many regions still remain underexplored. Under the hypothesis that these regions have new and diverse populations/species of Arachis, several expeditions were carried out since 2000 in Bolivia, to increase the documentation of the genus diversity. As a first result of these explorations, a new species of section Arachis with B genome is formally described. Arachis inflata is closely related to A. magna and A. ipaënsis, but it can be clearly distinguished from them, and from any other species of the genus, for having a type of fruit with a completely distinct morphology. The fruit has a smooth epicarp, but shows a bullated aspect, due to the presence of air chambers in the mesocarp.

Early and late leaf spot are two devastating diseases of peanut (Arachis hypogaea L.) worldwide. The development of a fertile, cross-compatible synthetic amphidiploid, TxAG-6 ([A. batizocoi × (A. cardenasii × A. diogoi)]4x), opened novel opportunities for the introgression of wild alleles for disease and pest resistance into commercial cultivars. Twenty-seven interspecific lines selected from prior evaluation of an advanced backcross population were evaluated for resistance to early and late leaf spot, and for yield in two locations in Ghana in 2006 and 2007. Several interspecific lines had early leaf spot scores significantly lower than the susceptible parent, indicating that resistance to leaf spot had been successfully introgressed and retained after three cycles of backcrossing. Time to appearance of early leaf spot symptoms was less in the introgression lines than in susceptible check cultivars, but the opposite was true for late leaf spot. Selected lines from families 43-08, 43-09, 50-04, and 60-02 had significantly reduced leaf spot scores, while lines from families 43-09, 44-10, and 63-06 had high pod yields. One line combined both resistance to leaf spot and high pod yield, and several other useful lines were also identified. Results suggest that it is possible to break linkage drag for low yield that accompanies resistance. However, results also suggest that resistance was diluted in many of the breeding lines, likely a result of the multigenic nature of resistance. Future QTL analysis may be useful to identify alleles for resistance and allow recombination and pyramiding of resistance alleles while reducing linkage drag.

'AG18' (Reg. no. CV-147, PI 698186) is a high-yielding, high-grading, high-oleic fatty acid, runner-type peanut (Arachis hypogaea L. ssp. hypogaea var. hypogaea) cultivar with good resistance to Sclerotinia blight (caused by Sclerotinia minor Jagger). The cultivar was developed by the Texas A&M AgriLife Research peanut breeding program to provide growers with a higher-yielding option when compared to the previously released 'Tamrun OL11' cultivar. AG18 was tested under the experimental designation of Tx121082 and was released in 2020. It maintains the high percentage of total sound mature kernels that Tamrun OL11 had, as well as the resistance to S. minor. However, it proved to have higher yield potential across environments and years than did Tamrun OL11. Additionally, the seed size of AG18 is smaller than that of Tamrun OL11 and closer to the past industry standard, 'Florunner', making it more attractive to manufacturers.

Water deficit and salinity are two major abiotic stresses that have tremendous effect on crop yield worldwide. Timely identification of these stresses can help limit associated yield loss. Confirmatory detection and identification of water deficit stress can also enable proper irrigation management. Traditionally, unmanned aerial vehicle (UAV)-based imaging and satellite-based imaging, together with visual field observation, are used for diagnostics of such stresses. However, these approaches can only detect salinity and water deficit stress at the symptomatic stage. Raman spectroscopy (RS) is a noninvasive and nondestructive technique that can identify and detect plant biotic and abiotic stress. In this study, we investigated accuracy of Raman-based diagnostics of water deficit and salinity stresses on two greenhouse-grown peanut accessions: tolerant and susceptible to water deficit. Plants were grown for 76 days prior to application of the water deficit and salinity stresses. Water deficit treatments received no irrigation for 5 days, and salinity treatments received 1.0 L of 240-mM salt water per day for the duration of 5-day sampling. Every day after the stress was imposed, plant leaves were collected and immediately analyzed by a hand-held Raman spectrometer. RS and chemometrics could identify control and stressed (either water deficit or salinity) susceptible plants with 95% and 80% accuracy just 1 day after treatment. Water deficit and salinity stressed plants could be differentiated from each other with 87% and 86% accuracy, respectively. In the tolerant accessions at the same timepoint, the identification accuracies were 66%, 65%, 67%, and 69% for control, combined stresses, water deficit, and salinity stresses, respectively. The high selectivity and specificity for presymptomatic identification of abiotic stresses in the susceptible line provide evidence for the potential of Raman-based surveillance in commercial-scale agriculture and digital farming.

The use of molecular markers in plant breeding has become a routine practice, but the cost per accession can be a hindrance to the routine use of Quantitative Trait Loci (QTL) identification in breeding programs. In this study, we demonstrate the use of targeted re-sequencing as a proof of concept of a cost-effective approach to retrieve highly informative allele information, as well as develop a bioinformatics strategy to capture the genome-specific information of a polyploid species. SNPs were identified from alignment of raw transcriptome reads (2 × 50 bp) to a synthetic tetraploid genome using BWA followed by a GATK pipeline. Regions containing high polymorphic SNPs in both A genome and B genomes were selected as targets for the resequencing study. Targets were amplified using multiplex PCR followed by sequencing on an Illumina HiSeq. Eighty-one percent of the SNP calls in diploids and 68% of the SNP calls in tetraploids were confirmed. These results were also confirmed by KASP validation. Based on this study, we find that targeted resequencing technologies have potential for obtaining maximum allele information in allopolyploids at reduced cost.

Estudios de compatibilidad cruzada en Arachis L. han sacado a la luz posibles nuevas fuentes de genes para introgresión en el maní cultivado. Se hicieron un total de 32 cruzamientos distintos, utilizando A. gregoryi C.E. Simpson, Krapov. & Valls accesión V14957 como progenitor femenino y especies de Arachis que contienen siete genomas distintos como progenitores masculinos. Las 3167 polinizaciones resultaron en 153 híbridos inter e intraespecíficos confirmados. Estimaciones de viabilidad del polen paternal por tinción (PVS) variaron de 46.75 a 99.17%, mientras que el recuento de polen de los híbridos varió de 0.30 a 43.60 %, ese PVS más alto resultando de una combinación intraespecífica, lo que sugiere variabilidad apreciable entre accesiones de A. gregoryi. Las estimaciones de viabilidad del polen paterno por germinación (PVG) resultaron en valores consistentemente más bajos para todos los materiales, que van desde 41.91% a los 88.00%. Arachis gregoryi es importante para expandir la diversidad disponible de especies asociadas con el genoma B del maní; tiene el potencial de incorporarse como progenitor en cruzamientos que apuntan a la expansión de la base genética del maní y puede ser útil para concentrar genes importantes en líneas de premejoramento asociadas al genoma B.

Identification of specific genotypes can be accomplished by visual recognition of their distinct phenotypical appearance, as well as DNA analysis. Visual identification (ID) of species is subjective and usually requires substantial taxonomic expertise. Genotyping and sequencing are destructive, time- and labor-consuming. In this study, we investigate the potential use of Raman spectroscopy (RS) as a label-free, non-invasive and non-destructive analytical technique for the fast and accurate identification of peanut genotypes. We show that chemometric analysis of peanut leaflet spectra provides accurate identification of different varieties. This same analysis can be used for prediction of nematode resistance and oleic-linoleic oil (O/L) ratio. Raman-based analysis of seeds provides accurate genotype identification in 95% of samples. Additionally, we present data on the identification of carbohydrates, proteins, fiber and other nutrients obtained from spectroscopic signatures of peanut seeds. These results demonstrate that RS allows for fast, accurate and non-invasive screening and selection of plants which can be used for precision breeding.

Cross-compatibility studies in Arachis L. have brought to light possible new sources of genes for introgression in cultivated peanuts. A total of 32 different crosses were made, using accession V14957 of A. gregoryi C.E. Simpson, Krapov. & Valls as the female parent and Arachis species containing seven distinct genomes as male parents. The 3167 pollinations resulted in 153 confirmed inter and intraspecific hybrids. Viability estimates of paternal pollen by staining (PVS) varied from 46.75 to 99.17%, while the pollen count of the hybrids varied from 0.3 to 43.6%, this highest PVS resulting from an intraspecific combination, which suggests appreciable variability in accessions of A. gregoryi. Viability estimates of paternal pollen by germination (PVG) resulted in consistently lower values for all materials, ranging from 41.91% to 88.00%. Arachis gregoryi is important to expand the available diversity of species associated with the peanut B genome; it has a potential to be incorporated as a parent in crosses that aim to expand the genetic base of peanuts and may be useful for concentrating important genes in pre-breeding lines associated with the B genome.

ABSTRACT Athelia rolfsii (Curzi) C.C. Tu & Kimbr. is the one of the most damaging pathogens of cultivated peanut, causing the soilborne disease known regionally as white mold, stem rot, or southern blight. Because the genetic base for cultivated peanut is narrow, wild Arachis species may possess novel sources of disease resistance. We evaluated 18 accessions representing 15 Arachis species (batizocoi, benensis, cardenasii, correntina, cruziana, diogoi, duranensis, herzogii, hoehnei, kempff-mercadoi, kuhlmannii, microsperma, monticola, simpsonii, williamsii) in the greenhouse for resistance to At. rolfsii. Assays were conducted on intact plants propagated from rooted cuttings inoculated with mycelial plugs, and lesion length and mycelial growth were measured at 4, 6, 10, and 12 days after inoculation. For lesion length, Arachis batizocoi (PI 468326 and PI 468327), and A. kuhlmannii PI 468159 were the most susceptible entries with a mean lesion length >50 mm at 12 days after inoculation. Arachis microsperma (PI 666096 and PI 674407) and A. diogoi PI 468354 had the shortest lesions with mean lengths ≤16 mm at 12 days after inoculation. Arachis cruziana PI 476003 and the two A. batizocoi PIs had the highest mean area under the disease progress curves (AUDPCs), and the lowest AUDPC was obtained from the A. microsperma PI 674407. Mycelial growth was correlated with lesion length in most species except A. monticola PI 497260. These results may be useful to peanut geneticists seeking additional sources of resistance to Athelia rolfsii.

Key messageQTL mapping of important architectural traits was successfully applied to an A-genome diploid population using gene-specific variations.AbstractPeanut wild species are an important source of resistance to biotic and possibly abiotic stress; because these species differ from the cultigen in many traits, we have undertaken to identify QTLs for several plant architecture-related traits. In this study, we took recently identified SNPs, converted them into markers, and identified QTLs for architectural traits. SNPs from RNASeq data distinguishing two parents, A. duranensis (KSSc38901) and A. cardenasii (GKP10017), of a mapping population were identified using three referencesA. duranensis V14167 genome sequence, and transcriptome sequences of A. duranensis KSSc38901 and OLin. More than 49,000 SNPs differentiated the parents, and 87.9% of the 190 SNP calls tested were validated. SNPs were then genotyped on 91 F-2 lines using KASP chemistry on a Roche LightCycler 480 and a Fluidigm Biomark HD, and using SNPType chemistry on the Fluidigm Biomark HD. A linkage map was constructed having ten linkage groups, with 144 loci spanning a total map distance of 1040cM. Comparison of the A-genome map to the A. duranensis genome sequence revealed a high degree of synteny. QTL analysis was also performed on the mapping population for important architectural traits. Fifteen definitive and 16 putative QTLs for petiole length, leaflet length and width, leaflet area, leaflet length/width ratio, main stem height, presence of flowers on the main stem, and seed mass were identified. Results demonstrate that SNPs identified from transcriptome sequencing could be converted to KASP or SNPType markers with a high success rate, and used to identify alleles with significant phenotypic effects, These could serve as information useful for introgression of alleles into cultivated peanut from wild species and have the potential to allow breeders to more easily fix these alleles using a marker-assisted backcrossing approach.