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At least 19 recordsLinked to original sources
PubMed2005

Taxonomic relationships among Arachis sect. Arachis species as revealed by AFLP markers.

Cultivated peanut, Arachis hypogaea L., is a tetraploid (2n = 4x = 40) species thought to be of allopolyploid origin. Its closest relatives are the diploid (2n = 2x = 20) annual and perennial species included with it in Arachis sect. Arachis. Species in section Arachis represent an important source of novel alleles for improvement of cultivated peanut. A better understanding of the level of speciation and taxonomic relationships between taxa within section Arachis is a prerequisite to the effective use of this secondary gene pool in peanut breeding programs. The AFLP technique was used to determine intra- and interspecific relationships among and within 108 accessions of 26 species of this section. A total of 1328 fragments were generated with 8 primer combinations. From those, 239 bands ranging in size from 65 to 760 bp were scored as binary data. Genetic distances among accessions ranged from 0 to 0.50. Average distances among diploid species (0.30) were much higher than that detected between tetraploid species (0.05). Cluster analysis using different methods and principal component analysis were performed. The resulting grouping of accessions and species supports previous taxonomic classifications and genome designations. Based on genetic distances and cluster analysis, A-genome accessions KG 30029 (Arachis helodes) and KSSc 36009 (Arachis simpsonii) and B-genome accession KGBSPSc 30076 (A. ipaensis) were the most closely related to both Arachis hypogaea and Arachis monticola. This finding suggests their involvement in the evolution of the tetraploid peanut species.

Arachis↗
PubMed1996

Identification of RAPD, SCAR, and RFLP markers tightly linked to nematode resistance genes introgressed from Arachis cardenasii into Arachis hypogaea.

Two dominant genes conditioning resistance to the root-knot nematode Meloidogyne arenaria were identified in a segregating F2 population derived from the cross of 4x (Arachis hypogaea x Arachis cardenasii)-GA 6 and PI 261942. Mae is proposed as the designation for the dominant gene restricting egg number and Mag is proposed as the designation for the dominant gene restricting galling. The high levels of resistance in GA 6 were introgressed from A. cardenasii and, therefore, a search to identify A. cardenasii specific RAPD markers that are tightly linked to these resistance genes was conducted utilizing bulked segregant analysis. One RAPD marker (Z3/265) was linked at 10 +/- 2.5 (SE) and 14 +/- 2.9 cM from Mag and Mae, respectively. The marker was mapped to linkage group 1 at 5 cM from Xuga.cr239 in the backcross map in an area where introgression from A. cardenasii had previously been reported. This fragment was cloned and used to generate a pair of primers that specifically amplified this locus (sequence characterized amplified region, SCAR) and as a RFLP probe. Their close linkage with the resistance genes will be useful in marker-based selection while transferring nematode resistance from introgression lines into elite breeding lines and cultivars. The Z3/265 marker associated with the genes Mae or Mag was not found in other highly resistant Arachis species (Arachis batizocoi or Arachis stenosperma), in progenies of interspecific crosses with A. cardenasii that were moderately resistant, or in the resistant A. hypogaea lines PI 259634 and PI 259572. These represent the first molecular markers linked with a resistant gene in peanut and the first report of two physiological responses to nematode attack associated with two genetic factors.

Animals↗
PubMed2001

Final report on the safety assessment of Peanut (Arachis hypogaea) Oil, Hydrogenated Peanut Oil, Peanut Acid, Peanut Glycerides, and Peanut (Arachis hypogaea) Flour.

Peanut (Arachis Hypogaea) Oil is the refined fixed oil obtained from the seed kernels of Arachis hypogaea. Hydrogenated Peanut Oil, Peanut Acid, and Peanut Glycerides are all derived from Peanut Oil. Peanut Flour is a powder obtained by the grinding of peanuts. The oils and glycerides function in cosmetic formulations as skin-conditioning agents. The acid functions as a surfactant-cleansing agent, and the flour functions as an abrasive, bulking agent and/or viscosity-increasing agent. In 1998, only Peanut Oil and Hydrogenated Peanut Oil were reported in use. When applied to the skin, Peanut Oil can enhance the absorption of other compounds. Hepatic changes were noted at microscopic examination of rats fed diets containing 15% edible Peanut Oil for 28 days, although no control group was maintained and the findings were also noted in rats fed fresh corn oil. United States Pharmacopeia (USP)-grade Peanut Oil was considered relatively nonirritating when injected into guinea pigs and monkeys. Technical-grade Peanut Oil was moderately irritating to rabbits and guinea pigs and mildly irritating to rats following dermal exposure. This same oil produced reactions in < or = 10% of 50 human males. Peanut Oil was not an ocular irritant in rabbits. Peanut Oil, either "laboratory expressed" or extracted using a food-grade solvent, was not carcinogenic to mice. Peanut Oil exerted anticarcinogenic activity when tested against known carcinogens. Peanuts are the food most likely to produce allergic and anaphylactic reactions. The major allergen is a protein that does not partition into Peanut Oil, Hydrogenated Peanut Oil, Peanut Acid, and Peanut Glycerides. Aflatoxins can be produced in stored agricultural crops such as peanuts, but do not partition into the oils, acids, or glycerides. Manufacturers were cautioned to make certain that the oils, acids, and glycerides are free of aflatoxins and protein. Formulators were cautioned that the oils, acids, or glycerides may enhance penetration and can affect the use of other ingredients whose safety assessment was based on their lack of absorption. The available studies on Peanut Oil supported the conclusion that Peanut Oil, Hydrogenated Peanut Oil, Peanut Acid, and Peanut Glycerides are safe for use in cosmetic formulations. Peanut (Arachis Hypogaea) Flour, however, is sufficiently different from the above ingredients such that its safety can not be supported by studies using the oil. The additional data needed for Peanut (Arachis Hypogaea) Flour are (1) concentration of use; (2) chemical specifications (i.e., aflatoxin and protein levels); (3) method of preparation; and (4) contact urticaria and dermal sensitization at concentration of use. Although data on aflatoxin levels are sought, it is expected that concentrations of aflatoxin should comply with U.S. government stipulations. Absent the additional data, it was concluded that the available data are insufficient to support the safety of Peanut (Arachis Hypogaea) Flour for use in cosmetic products.

Administration, Cutaneous↗
PubMed2005

Genomic affinities in Arachis section Arachis (Fabaceae): molecular and cytogenetic evidence.

Section Arachis is the largest of nine sections in the genus Arachis and includes domesticated peanut, A. hypogaea L. Most species are diploids (x = 10) with two tetraploids and a few aneuploids. Three genome types have been recognized in this section (A, B and D), but the genomes are not well characterized and relationships of several newly described species are uncertain. To clarify genomic relationships in section Arachis, cytogenetic information and molecular data from amplified fragment length polymorphism (AFLP) and the trnT-F plastid region were used to provide an additional insight into genome composition and species relationships. Cytogenetic information supports earlier observations on genome types of A. cruziana, A. herzogii, A. kempff-mercadoi and A. kuhlmannii but was inconclusive about the genome composition of A. benensis, A. hoehnei, A. ipaensis, A. palustris, A. praecox and A. williamsii. An AFLP dendrogram resolved species into four major clusters and showed A. hypogaea grouping closely with A. ipaensis and A. williamsii. Sequence data of the trnT-F region provided genome-specific information and showed for the first time that the B and D genomes are more closely related to each other than to the A genome. Integration of information from cytogenetics and biparentally and maternally inherited genomic regions show promise in understanding genome types and relationships in Arachis.

Arachis↗
PubMed2000

A comparison study on allergen components between Korean (Arachis fastigiata Shinpung) and American peanut (Arachis hypogaea Runner).

The prevalence of peanut allergy in Korea is lower than in America. Peanut extract allergens between the two countries have not been standardized. This study was performed to compare the allergenicity of raw Korean and American peanuts with that of roasted peanuts. We prepared the peanut extracts in Korean raw (KP) and roasted peanuts (KRP), and also in American raw (AP) and roasted (ARP) peanuts. We compared the peanut extract allergens of KP, KRP, AP and ARP in vitro with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting, T-cell proliferation assay and skin prick test with sera from peanut-allergic patients. SDS-PAGE and Western blotting demonstrated four allergenic extracts, numerous bands that displayed a high prevalence of IgE binding. IgE-binding bands were at 64, 36 and 17 kDa. Western blot inhibition revealed that either KP or AP could almost completely inhibit the reactivity of the other extract. There were no differences between T-cell proliferation assay and skin prick test. In conclusion, this investigation showed no different allergic components in both raw and roast extracts of Korean and American peanuts.

Allergens↗
PubMed2004

Genetic diversity of peanut (Arachis hypogaea L.) and its wild relatives based on the analysis of hypervariable regions of the genome.

BACKGROUND: The genus Arachis is native to a region that includes Central Brazil and neighboring countries. Little is known about the genetic variability of the Brazilian cultivated peanut (Arachis hypogaea, genome AABB) germplasm collection at the DNA level. The understanding of the genetic diversity of cultivated and wild species of peanut (Arachis spp.) is essential to develop strategies of collection, conservation and use of the germplasm in variety development. The identity of the ancestor progenitor species of cultivated peanut has also been of great interest. Several species have been suggested as putative AA and BB genome donors to allotetraploid A. hypogaea. Microsatellite or SSR (Simple Sequence Repeat) markers are co-dominant, multiallelic, and highly polymorphic genetic markers, appropriate for genetic diversity studies. Microsatellite markers may also, to some extent, support phylogenetic inferences. Here we report the use of a set of microsatellite markers, including newly developed ones, for phylogenetic inferences and the analysis of genetic variation of accessions of A. hypogea and its wild relatives. RESULTS: A total of 67 new microsatellite markers (mainly TTG motif) were developed for Arachis. Only three of these markers, however, were polymorphic in cultivated peanut. These three new markers plus five other markers characterized previously were evaluated for number of alleles per locus and gene diversity using 60 accessions of A. hypogaea. Genetic relationships among these 60 accessions and a sample of 36 wild accessions representative of section Arachis were estimated using allelic variation observed in a selected set of 12 SSR markers. Results showed that the Brazilian peanut germplasm collection has considerable levels of genetic diversity detected by SSR markers. Similarity groups for A. hypogaea accessions were established, which is a useful criteria for selecting parental plants for crop improvement. Microsatellite marker transferability was up to 76% for species of the section Arachis, but only 45% for species from the other eight Arachis sections tested. A new marker (Ah-041) presented a 100% transferability and could be used to classify the peanut accessions in AA and non-AA genome carriers. CONCLUSION: The level of polymorphism observed among accessions of A. hypogaea analyzed with newly developed microsatellite markers was low, corroborating the accumulated data which show that cultivated peanut presents a relatively reduced variation at the DNA level. A selected panel of SSR markers allowed the classification of A. hypogaea accessions into two major groups. The identification of similarity groups will be useful for the selection of parental plants to be used in breeding programs. Marker transferability is relatively high between accessions of section Arachis. The possibility of using microsatellite markers developed for one species in genetic evaluation of other species greatly reduces the cost of the analysis, since the development of microsatellite markers is still expensive and time consuming. The SSR markers developed in this study could be very useful for genetic analysis of wild species of Arachis, including comparative genome mapping, population genetic structure and phylogenetic inferences among species.

Alleles↗
PubMed2003

A large scale analysis of resistance gene homologues in Arachis.

Arachis hypogaea L., commonly known as the peanut or groundnut, is an important and widespread food legume. Because the crop has a narrow genetic base, genetic diversity in A. hypogaea is low and it lacks sources of resistance to many pests and diseases. In contrast, wild diploid Arachis species are genetically diverse and are rich sources of disease resistance genes. The majority of known plant disease resistance genes encode proteins with a nucleotide binding site domain (NBS). In this study, degenerate PCR primers designed to bind to DNA regions encoding conserved motifs within this domain were used to amplify NBS-encoding regions from Arachis spp. The Arachis spp. used were A. hypogaea var. Tatu and wild species that are known to be sources of disease resistance: A. cardenasii, A. duranensis, A. stenosperma and A. simpsonii. A total of 78 complete NBS-encoding regions were isolated, of which 63 had uninterrupted ORFs. Phylogenetic analysis of the Arachis NBS sequences derived in this study and other NBS sequences from Arabidopsis thaliana, Medicago trunculata, Glycine max, Lotus japonicus and Phaseolus vulgaris that are available in public databases This analysis indicates that most Arachis NBS sequences fall within legume-specific clades, some of which appear to have undergone extensive copy number expansions in the legumes. In addition, NBS motifs from A. thaliana and legumes were characterized. Differences in the TIR and non-TIR motifs were identified. The likely effect of these differences on the amplification of NBS-encoding sequences by PCR is discussed.

Arabidopsis↗
PubMed2001

[Studies on transference of hydrogenase genes of Rhizobium arachis].

The hydrogen-uptake genes were transferred into wild Rhizobium arachis Ra strains (Hup-, Nif+, Apr) by triparental mating using pRK2013 as help plasmid. A transconjugant R. arachis Rz34-2(Hup+, Nif+, Apr, Tcr) which expressed high activities of hydrogenase and nitrogenase under free-living and symbiotic state was screened. Peanut inoculation test with recipient R. arachis Ra34, transcojugant Rz34-2 and control strain R. arachis L8-3 (Hup+, Nif+) was carried out respectively. The results showed that, compare to treatment without inoculation, inoculation with R. arachis Ra34 and R. arachis L8-3, the dry weight of leaf inoculated with transconjuant Rz34-2 increased 6.2%, 7.6% and 6.3% respectively; the N-content of seed increased 8.8%, 10.0% and 6.0%; the output increased 18.8%, 10.5% and 10.7%. This suggested that legume plants inoculated with Rhizobium strains (Hup+) were more efficient to accumulate N and to increase its output.

Arachis↗
PubMed1992

Use of single-primer DNA amplifications in genetic studies of peanut (Arachis hypogaea L.).

A recent approach to detecting genetic polymorphism involves the amplification of genomic DNA using single primers of arbitrary sequence. When separated electrophoretically in agarose gels, the amplification products give banding patterns that can be scored for genetic variation. The objective of this research was to apply these techniques to cultivated peanut (Arachis hypogaea L.) and related wild species to determine whether such an approach would be feasible for the construction of a genetic linkage map in peanut or for systematic studies of the genus. Two peanut cultivars, 25 unadapted germplasm lines of A. hypogaea, the wild allotetraploid progenitor of cultivated peanut (A. monticola), A. glabrata (a tetraploid species from section Rhizomatosae), and 29 diploid wild species of Arachis were evaluated for variability using primers of arbitrary sequence to amplify segments of genomic DNA. No variation in banding pattern was observed among the cultivars and germplasm lines of A. hypogaea, whereas the wild Arachis species were uniquely identified with most primers tested. Bands were scored (+/-) in the wild species and the PAUP computer program for phylogenetic analysis and the HyperRFLP program for genetic distance analysis were used to generate dendrograms showing genetic relationships among the diploid Arachis species evaluated. The two analyses produced nearly identical dendrograms of species relationships. In addition, approximately 100 F2 progeny from each of two interspecific crosses were evaluated for segregation of banding patterns. Although normal segregation was observed among the F2 progeny from both crosses, banding patterns were quite complex and undesirable for use in genetic mapping. The dominant behavior of the markers prevented the differentiation of heterozygotes from homozygotes with certainty, limiting the usefulness of arbitrary primer amplification products as markers in the construction of a genetic linkage map in peanut.

Arachis↗
PubMed2006

Chromosomal and phylogenetic context for conglutin genes in Arachis based on genomic sequence.

Comparative genomic and cDNA sequence analysis of ara h 2, a major peanut allergen, and a related conglutin ara h 6 were performed in Arachis hypogaea L. and its putative progenitors, Arachis duranensis and Arachis ipaensis. The complete identity between sequences encoding Ara h 2 isoforms demonstrated that these are homeologous genes and represent orthologs from diploid ancestors. Three copies of ara h 6 were identified in A. hypogaea, one of them located in the A-genome and the other two in the B-genome. Expression analysis showed higher levels of ara h 2 transcripts compared with ara h 6. Dual-labeled genomic in situ hybridization permitted identification of two subgenomes, each of which contained one pair of ara h 2-ara h 6 signals localized by fluorescence in situ hybridization. Characterization of genomic clones showed close genetic linkage between Ara h 2.02 and one copy of ara h 6 in the B-genome. The physical linkage may have arisen by tandem duplication and divergence of an ancestral gene. A gene duplication event specific to the B-genome progenitor has resulted in ara h 6 paralogs. These data provide further evidence for progenitor relationships and genomic organization of the conglutin gene family in the genus Arachis and could contribute to the development of a hypoallergenic peanut.

Arachis↗
PubMed2001

RAPD and ISSR fingerprints as useful genetic markers for analysis of genetic diversity, varietal identification, and phylogenetic relationships in peanut (Arachis hypogaea) cultivars and wild species.

Abstract: Twenty-one random and 29 SSR primers were used to assess genetic variation and interrelationships among subspecies and botanical varieties of cultivated peanut, Arachis hypogaea (2n = 4x = 40), and phylogenetic relationships among cultivated peanut and wild species of the genus Arachis. In contrast with the previous generalization that peanut accessions lack genetic variation, both random and SSR primers revealed 42.7 and 54.4% polymorphism, respectively, among 220 and 124 genetic loci amplified from 13 accessions. Moreover, the dendrograms based on RAPD, ISSR, and RAPD + ISSR data precisely organized the five botanical varieties of the two subspecies into five clusters. One SSR primer was identified that could distinguish all the accessions analysed within a variety. Although the polymorphic index content varied from 0.1 to 0.5 for both ISSR and RAPD markers, primer index values were substantially higher for RAPD primers (0.35-4.65) than for SSR primers (0.35-1.73). It was possible to identify accessions, particularly those of divergent origins, by RAPD and (or) ISSR fingerprints. Based on these results, marker-based genetic improvement in A. hypogaea appears possible. None of the 486 RAPD and 330 ISSR amplification products were found to be commonly shared among 13 species of section Arachis and one species each of sections Heteranthae, Rhizomatosae, and Procumbentes. Dendrograms constructed from RAPD, ISSR, and RAPD + ISSR data showed overall similar topologies. They could be resolved into four groups corresponding to the species grouped in four taxonomic sections. The present results strongly support the view that Arachis monticola (2n = 4x = 40) and A. hypogaea are very closely related, and indicate that A. villosa and A. ipaensis are the diploid wild progenitors of these tetraploid species.

Arachis↗
PubMed2005

A microsatellite-based, gene-rich linkage map for the AA genome of Arachis (Fabaceae).

Cultivated peanut (Arachis hypogaea) is an important crop, widely grown in tropical and subtropical regions of the world. It is highly susceptible to several biotic and abiotic stresses to which wild species are resistant. As a first step towards the introgression of these resistance genes into cultivated peanut, a linkage map based on microsatellite markers was constructed, using an F(2) population obtained from a cross between two diploid wild species with AA genome (A. duranensis and A. stenosperma). A total of 271 new microsatellite markers were developed in the present study from SSR-enriched genomic libraries, expressed sequence tags (ESTs), and by "data-mining" sequences available in GenBank. Of these, 66 were polymorphic for cultivated peanut. The 271 new markers plus another 162 published for peanut were screened against both progenitors and 204 of these (47.1%) were polymorphic, with 170 codominant and 34 dominant markers. The 80 codominant markers segregating 1:2:1 (P<0.05) were initially used to establish the linkage groups. Distorted and dominant markers were subsequently included in the map. The resulting linkage map consists of 11 linkage groups covering 1,230.89 cM of total map distance, with an average distance of 7.24 cM between markers. This is the first microsatellite-based map published for Arachis, and the first map based on sequences that are all currently publicly available. Because most markers used were derived from ESTs and genomic libraries made using methylation-sensitive restriction enzymes, about one-third of the mapped markers are genic. Linkage group ordering is being validated in other mapping populations, with the aim of constructing a transferable reference map for Arachis.

Arachis↗
PubMed2001

Genome size in Arachis duranensis: a critical study.

Arachis duranensis is a diploid wild relative of the tetraploid cultivated peanut Arachis hypogaea. The literature indicates two 2C genomic DNA mean values (genome size) for A. duranensis, 4.92 and 5.64 pg, and intraspecific variation of up to 11% negatively correlated with altitude above sea level of the collection sites has been reported. Our recent investigations of Arachis species have shown that unrecognized technical problems with peanut material may have influenced previous genome-size data and rendered them open to critical comments. In the present study, 20 accessions of A. duranensis were investigated by means of DNA flow cytometry (propidium iodide staining) and several of these also by Feulgen DNA image analysis. Pisum sativum was used as the internal standard (2C = 8.84 pg). 2C values in A. duranensis were about half those described previously and varied between 2.49 and 2.87 pg (flow cytometry). This variation was statistically significant and reproducible. There was a negative correlation of genome size with latitude and altitude above sea level of the collection sites. Such a correlation had been already found in one of the previous studies. However, the incongruences between the absolute DNA content values obtained in the present investigation and those in the literature point to the importance of carrying out methodological studies on best practice in DNA-content determinations in plants.

Arachis↗
PubMed1984

Intestinal motility after infusion of arachis oil into duodenum and ileum of dogs.

Arachis oil and a mixture of arachis oil with bile and pancreatic enzymes were infused into the duodenum and ileum of dogs via surgically positioned catheters in order to study the mechanism of disruption of the migrating complex by intraluminally infused triglycerides, the importance of cholecystokinin and neurotensin in this event, and the pattern of digestive myoelectrical activity during fat digestion. When infused into the duodenum both arachis oil and the oil-bile-pancreatic enzyme mixture disrupted the migrating myoelectric complex (MMC). When infused into the ileum, only the oil-bile-pancreatic enzyme mixture disrupted the MMC. The duration of the disruption lasted as long as when the same amount of oil was administered orally. Triglyceride-induced digestive activity was characterized by the frequent alternation of short periods of spiking activity and short periods of quiescence. It is concluded that the triglyceride-induced disruption of the MMC-pattern is not caused by the triglyceride itself but by some emulsion or digestion product. We further suggest that the disruption is hormonally mediated and due to fat-stimulated neurotensin, rather than cholecystokinin (CCK), release.

Administration, Oral↗
PubMed1982

Extent of desialation of blood group MM, NN, and MN antigens required for reactivity with human anti-T antibody and Arachis hypogaea lectin.

Immunochemical activity of the Arachis hypogaea lectin has been equated, in spite of its different hapten combining requirements, with that of the human anti-T (Thomsen-Friedenreich) antibody population which is of importance in cancer immunology. We show here by gradual desialation of isolated human blood group MM and NN antigens at pH 2.0, 56 degrees C, that A. hypogaea lectin is, in addition, substantially more tolerant to NeuAc in the vicinity of T antigen's immunodominant repeating structures, Gal beta 1 leads to 3 GalNAc, than human anti-T antibodies. Reactivity with the Arachis lectin appeared first at 20-25% release of NeuAc from the antigens, whereas faint reactivity with anti-T was first recognizable at 50-55% NeuAc release from NN and 65-70% from MM antigen. Remarkably, at these degrees of desialation, the NN and MM antigens had about 50% of maximal activity toward the Arachis lectin. The slower appearance of T antigen upon graded desialation of MM antigen is likely due to the higher concentration of NeuAc and difference in some of its linkages on intact MM as compared to NN antigen.

Antibodies↗
PubMed2026

The curious case of sporadic nematode susceptibility in "Tifguard" peanut (Arachis hypogaea): seed mixture or genetic instability?

The Runner-type peanut (Arachis hypogaea L.) cultivar "Tifguard" carries an introgressed chromosomal segment on chromosome A09 from A. cardenasii that confers resistance to root-knot nematode (RKN). Despite this, a proportion of "Tifguard" plants show RKN symptoms, which could plausibly be attributed to seed mixture or outcrossing. However, recent work has shown that cultivated peanut exhibits surprisingly frequent large-scale chromosomal instability (1% to 5%); suggesting that resistance loss could arise from spontaneous structural genomic change. To test these possibilities, we grew foundation seed in an RKN-infested field and collected symptomatic and asymptomatic plants. Lineages derived by single-seed descent were genotyped using the Axiom Arachis 48K SNP array v2 and whole-genome sequencing. Symptomatic lineages lacked the A. cardenasii introgression on chromosome A09 and instead carried the complete endogenous A. hypogaea A09 region at the expected dosage. There was no evidence of large-scale homoeologous exchange, deletion, or other genomic instability affecting this chromosome. Most susceptible plants were closely related to resistant "Tifguard" but lacked the A09 introgression, with a smaller proportion assignable to known nematode-susceptible cultivars, implicating seed mixture with a possible contribution from cross-pollination rather than genomic instability. Because resistance depends on a single major-effect segment, rare events have disproportionate phenotypic impact, placing high demands on genetic purity. For important traits conferred by major loci, marker-based testing across seed-increase stages could verify trait retention directly, and is increasingly practical as marker costs decline.

Arachis↗