F1 Progeny Research Articles

Metabolomic Analysis Identifies Differences Between Wild and Domesticated Chili Pepper Fruits During Development (Capsicum annuum L.).

Capsicum spp. members are a rich source of specialized compounds due to their secondary metabolism. Some metabolic pathways have suffered modifications during the domestication process and improvement of agricultural traits. Here, we compared non-targeted LC–MS profiles from several areas: wild accessions (C. annuum L. var. glabriusculum), domesticated cultivars (C. annuum L.), and the F1 progeny of a domesticated, and a wild accession cross (in both directions) throughout seven stages of fruit development of chili pepper fruits. The main detected differences were in glycerophospholipid metabolism, flavone and flavonol biosynthesis, sphingolipid metabolism, and cutin biosynthesis. The domesticated group exhibited a higher abundance in 12′-apo-β-carotenal, among others capsorubin, and β-tocopherol. Palmitic acid and derivates, terpenoids, and quercitrin were prevalent in the wild accessions. F1 progeny showed a higher abundance of capsaicin, glycol stearate, and soyacerebroside I. This work supports evidence of the side-affectation of trait selection over the metabolism of chili pepper fruit development. Furthermore, it was also observed that there was a possible heterosis effect over the secondary metabolism in the F1 progeny.

Morpho-Agronomic Evaluation of Lagenaria siceraria Landraces and Their F1 Populations.

Lagenaria siceraria is one of the most important cucurbitaceous vegetables due to its prolific bearing habit, its edibility as a cooked vegetable, and its low cost of cultivation. The objective of this study was to evaluate variation in the morpho-agronomic traits among selected landraces and their F1 populations. The landraces were crossed based on the North Carolina II genetic design to develop F1 populations. The twelve F1 populations along with seven parental landraces were grown in a randomized complete block design with three replications. Significant differences (p < 0.05) were observed among quantitative traits suggesting considerable genetic variability. The genotypes displayed significant variation in most qualitative traits of fruits and seeds. The first five principal components of quantitative traits among the evaluated 19 genotypes contributed 74.84% of the variability. The biplot and dendrogram clustered the genotypes into five clusters according to their vegetative, fruit, and seed traits. The highest value for the broad-sense heritability estimate was recorded for days to edible harvest maturity trait. The F1 progenies were more variable than the landraces and can therefore be used for further Lagenaria siceraria genetic improvement.

INFLUENCE OF FERMENTATION TIME ON THE SENSORY QUALITY OF ARABICA COFFEE GENOTYPES IN GUATEMALA

In recent years, the Guatemalan coffee plantations have suffered a decline in its yield as a result of coffee rust. The use of cultivars resistant to this disease and with the potential to produce coffee with good drinking quality is essential for the sustainability of coffee cultivation in the country. The aim of this study was to analyze bean quality potential and the sensory profile of rust-resistant Arabica coffee genotypes as a function of different times of biological fermentation. The experiment was carried out in July 2014, at El Panorama farm, located in the municipality of San Rafael Pie de La Cuesta, Department of San Marcos, Guatemala. Eight rust resistant F5 progenies were tested and cultivars Marsellesa and Bourbon Amarelo were used as controls. Each genotype was subjected to two times of biological fermentation in water, after peeling (24 and 72 h). The experimental design was randomized complete blocks with three replications, in a 10 (genotypes) × 2 (times) factorial scheme, totaling 60 experimental units. The quality, sensory profile and granulometry of the treatments were evaluated. All the rust-resistant genotypes studied showed potential to produce specialty coffees in Guatemala and a superior granulometry in relation to Bourbon Amarelo. Marsellesa and Bourbon Amarelo obtained higher final scores and the attributes flavor, aftertaste, acidity, body, balance and overall were more accentuated. The time of biological fermentation did not influence the final score of the coffee (total score in the SCA protocol); however, there was a change in the sensory profile, with emphasis on cultivar Marsellesa, which increased the frequency of fruity notes and reduced caramel notes with longer fermentation time.

A high-density genetic map from a cacao F2 progeny and QTL detection for resistance to witches’ broom disease

A high-density genetic map from a cacao F2 progeny and QTL detection for resistance to witches’ broom disease

A sublethal concentration of afidopyropen suppresses the population growth of the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae)

The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is an important insect pest of cotton crops worldwide. The objectives of this study were to determine the acute toxicity of afidopyropen and whether there are any effects of sublethal concentrations of afidopyropen on the biological characteristics of A. gossypii. The results showed that afidopyropen possesses high acute toxicity to adult A. gossypii with a 72 h LC50 value of 1.062 mg L–1. A sublethal concentration (LC10) of afidopyropen significantly decreased adult longevity, fecundity and oviposition days of female adults in both F0 and F1 generations. The total pre-adult survival of F1 progeny was also significantly reduced by 30% at the LC10 of afidopyropen. In addition, the nymph developmental time, pre-adult period, adult pre-reproductive period (APRP), and total pre-reproductive period (TPRP) of the F1 progeny were significantly prolonged compared with the control. Several population parameters, including the net reproductive rate (R0), intrinsic rate of increase (r) and finite rate of increase (λ) of F1 progeny were significantly decreased by a sublethal afidopyropen concentration exposure. These results indicated that sublethal concentration of afidopyropen can significantly suppress A. gossypii population growth. It would be useful for assessing the overall effects of afidopyropen on A. gossypii.

Retraction Note: Selective inheritance of target genes from only one parent of sexually reproduced F1 progeny in Arabidopsis

Retraction Note: Selective inheritance of target genes from only one parent of sexually reproduced F1 progeny in Arabidopsis

Introgression of anthracnose resistance gene(s) into common bean (Phaseolus vulgaris)

Abstract. Kazimoto GK, Nchimbi-Msolla SF, Mabagala RB. 2022. Introgression of anthracnose resistance gene(s) into common bean (Phaseolus vulgaris). Cell Biol Dev 6: 20-31. Common bean anthracnose disease caused by the fungus Colletotrichum lindemuthianum causes significant yield losses. It is most destructive in areas with cool temperatures and high humidity (90-100%). The study aimed to introduce resistance genes into adapted but susceptible local cultivars of Masai Red and Soya Njano using conventional breeding methods. Five races of C. lindemuthianum were isolated and named from thirty-two common bean-diseased plant samples collected from Northern Tanzania. The sources of resistant genes were bean cultivars G2333 and AB136. Early developed populations were evaluated under field conditions in high altitude and humid environments at Bashnet in the Manyara region, in the Northern highlands of Tanzania. Both F2 and F3 populations of Soya Njano x G2333 were segregated for C. lindemuthianum resistance at a 9:7 ratio. Such segregation implied that two dominant epistatic genes conferred from G2333, the resistance being in the mode of epistatic gene interaction. The crosses between Masai Red x G2333 and F2 and F3 populations segregation ratio was 10:6, implying two dominant resistant genes were transferred to developed populations. The F2 and F3 progenies obtained from crossing Soya Njano and AB136 showed a ratio of 3:1. The F2 progenies from a cross between Masai Red and AB136 were segregated at a ratio of 3:1 and F3 progenies were 3:1. The 3:1 ratio confirmed single dominant gene inheritance conferred to developed progenies. The heritability (h²) from populations of Soya Njano x G2333 and Masai Red x G2333 was between 0.41 and 0.45. While Soya Njano, Masai Red, and A136 were between 0.2 and 0.53, which implied moderate heritability. F2 and F3 populations developed need further testing using MAS to confirm the presence of resistant genes. Multi-location testing should be done to verify the resistance levels of the developed bean population in later generations.

Rhyzopertha dominica Fabricius (Coleoptera: Bostrichidae): Growth and Developement on Six Different Varieties of Maize (Zea mays L.)

The research aimed to evaluate the Rhyzoperta dominica growth and development on six maize varieties. The No-choice method was adopted to evaluate the R. dominica life cylce from February to September 2018. Based on the result, the R. dominica growth and development were appropriate to be examined by the number of eggs, larvae, pupae, and F1 progenies and the percentage of weight loss rather than using the development time, the stage of development time, the median development time, the growth index of larvae, the potential of biotic, and susceptibility index. The development and the median development time were positively correlated with number of eggs, larvae, pupae, and F1 progenies. The R. dominica growth and development were faster on maize ‘ROK’ variety than other maize varieties. The highest number of eggs, larvae, pupae, and F1 progenies and the percentage of weight loss were detected on ‘ROK’ variety. On the other hand, the lowest growth and the longest development were observed on ‘Anoman’ variety. The variation of the R. dominica growth and development was due to the variation of the physical and biochemical characteristics of maize varieties.

Enabling Medicago truncatula forward genetics: identification of genetic crossing partner for R108 and development of mapping resources for Tnt1 mutants.

Though Medicago truncatula Tnt1 mutants are widely used by researchers in the legume community, they are mainly used for reverse genetics because of the availability of the BLAST-searchable large-scale flanking sequence tags database. However, these mutants should have also been used extensively for forward genetic screens, an effort that has been hindered due to the lack of a compatible genetic crossing partner for the M. truncatula genotype R108, from which Tnt1 mutants were generated. In this study, we selected three Medicago HapMap lines (HM017, HM018 and HM022) and performed reciprocal genetic crosses with R108. After phenotypic analyses in F1 and F2 progenies, HM017 was identified as a compatible crossing partner with R108. By comparing the assembled genomic sequences of HM017 and R108, we developed and confirmed 318 Indel markers evenly distributed across the eight chromosomes of the M. truncatula genome. To validate the effectiveness of these markers, by employing the map-based cloning approach, we cloned the causative gene in the dwarf mutant crs isolated from the Tnt1 mutant population, identifying it as gibberellin 3-β-dioxygenase 1, using some of the confirmed Indel markers. The primer sequences and the size difference of each marker were made available for users in the web-based database. The identification of the crossing partner for R108 and the generation of Indel markers will enhance the forward genetics and the overall usage of the Tnt1 mutants.

Comparative Bioactivity of Bamboo Leaf Ash and Bularafa Diatomaceous Earth against Maize Weevil (Sitophilus zeamais Motschulsky)

Maize is one of the major staple foods in Sub-Saharan Africa and there is serious loss in maize storage due to insect damage. This study compared the bioactivity of Bamboo Leaf Ash (BLA) and Bularafa Diatomaceous Earth (BDE) against Maize Weevil (Sitophilus zeamais Motschulsky) under laboratory conditions. Insecto®, a commercialized DE was also tested as standard check. Adults of the insects were exposed on maize admixed with the BLA at dose rate of 5,000, 10,000 and 20,000ppm; BDE and insecto® at a dose rate of 1,000ppm, at 28.20C and 82.2% relative humidity. Mortality increased with increasing exposure duration and all treatments showed mortality of more than 80% after 14days post-treatment compared to negative control with 0%.The treatments suppressed F1 progeny. Treated grains have weight loss less than 4%, kennel damage less than 14% and grain germination showed no significant change. The decreasing efficacy of the dusts against this insect is Insecto®&gt; BLA &gt; BDE. BLA and BDE have potential for the management of insect pests of stored grain in Nigeria.

Social Isolation Stress Modulates Pregnancy Outcomes and the Inflammatory Profile of Rat Uterus.

Prenatal stressors have been linked to adverse pregnancy outcomes; including preterm birth (PTB). Recent work demonstrates that social isolation in mothers represents a silent stressor contributing to PTB risk. Here; we investigate the association of inflammatory and stress markers with PTB risk in Long–Evans rats exposed to social isolation stress (SIS) during preconception and pregnancy across four generations (F0-F3). Gestational length; blood glucose; corticosterone levels; and maternal and offspring weights were assessed in two SIS paradigms: transgenerational (TG) and multigenerational (MG) exposure. Maternal uterine tissues were collected 21 days after the dams gave birth. Exposure to SIS reduced pregnancy lengths in the parental generation and neonatal birth weights in the F1 and F2 generations. Interleukin (IL)-1β (Il1b) mRNA levels increased in F0 animals but decreased in the offspring of both stress lineages. Protein levels of IL-1β decreased in the TG lineage. Corticotrophin-releasing hormone receptor 1 (Crhr1) expression decreased in SIS-exposed F0 animals and increased in the TG-F2 and MG-F1 offspring. Expression of enzyme 11-β hydroxysteroid dehydrogenase-2 (11bHSD2) was enhanced in F1 animals. These findings suggest SIS has adverse consequences on the F0 mothers; but their F1–F3 progeny may adapt to this chronic stress; thus supporting the fetal programming hypothesis.

Toxic and repellent impacts of botanical oils against Callosobruchus maculatus (Bruchidae: Coleoptera) in stored cowpea [Vigna unguiculata (L.) Walp.

Cowpea (Vigna unguiculata) is an important legume which is consumed globally for protein intake, particularly in Asian states. It is a well-known source of dietary fiber, protein, minerals, and vitamins. The cowpea grains are stored after harvest and used till the next harvest. However, the grains are infested by storage pests, primarily Callosobruchus maculatus. Hence, effective management strategies are needed to protect the stored grains form the pests. This study assessed the efficacy of some edible oils in suppressing C. maculatus infestation in stored cowpea grains. Four different botanical oils (i.e., mustard, neem, poppy, and pumpkin) at four different concentrations (i.e., 0.5, 1.0, 1.5 and 2.0 ml per 100 g grain) were included in the study. A control treatment without any botanical oil was also included for comparison. The relevant concentrations of botanical oils were poured into plastic containers containing 100 g cowpea grains and ten C. maculatus adults were released. The jars were sealed and placed at room temperature. Data relating to mortality, oviposition, F1 adult emergence, and seed weight loss were recorded. The tested botanical oils and their concentrations significantly affected mortality after one day. Mortality after 2nd and 3rd days remained unaffected by botanical oils and their different concentrations. The highest mortality was recorded in neem oil-treated grains followed by poppy, pumpkin, and mustard oils. Increased oviposition rate was observed in the grains treated with mustard and pumpkin oils, while those treated with neem and poppy oil recorded decreased oviposition. The control treatment had increased oviposition rate compared to tested botanical oils. All botanical oils significantly inhibited egg laying percentage. The highest germination was recorded for the grains treated with mustard oil followed by pumpkin, poppy, and neem oils, respectively. The lowest germination was recorded for control treatment. Significant differences were noted for C. maculatus repellency among botanical oils. No emergence of adults (F1 progeny) was recorded in all tested botanical oils; thus, F1 progeny was inhibited by 100%. Weight loss, damage percentage, and holes in the grains were not recorded since F1 progeny did not emerge. It is concluded that tested botanical oils are promising and could be utilized to control C. maculatus in cowpea grains during storage.

Cross-Resistance Pattern and Genetic Studies in Spirotetramat-Resistant Citrus Red Mite, Panonychus citri (Acari: Tetranychidae)

In the laboratory, an acaricide-susceptible strain of the citrus red mite, Panonychus citri (McGregor) (LS-FJ), was used to screen for resistance to spirotetramat. A spirotetramat-resistant strain (ST-NK) obtained after continuous selections through 15 selection cycles (45 generations) exhibited 1668.4-fold greater resistance when compared to the parent generation. Instability of the spirotetramat resistance in the mites was observed during 11 months under spirotetramat-free laboratory conditions. Cross-resistance to spirodiclofen and spiromesifen was detected both in eggs and larvae, but not to five other tested acaricides. Probit lines for F1 heterozygous progeny indicated that the resistance to spirotetramat in the mites was autosomal with neither sex linkage nor maternal effects. The degrees of dominance were 0.15 and 0.23 for the diploid F1 of LS-FJ♀ × ST-NK♂ and ST-NK♀ × LS-FJ♂, and 0.07 and 0.13 for haploid F2 of LS-FJ♀ × ST-NK♂ and ST-NK♀ × LS-FJ♂, respectively, which indicated that the resistance was incompletely dominant. The χ2 analyses from the response of a backcross of crossed F1 progeny and ST-NK and F2 progeny showed that multiple genes are responsible for resistance to spirotetramat.

Split-Cre mediated deletion of DNA no longer needed after site-specific integration in rice.

N-cre and C-cre added in separate lines reassemble functional Cre in F1 progeny to excise unnecessary DNA, includingcre DNA, thereby eliminating generations needed to cross in and outcre. Crop improvement via transgenesis can benefit through efficient DNA integration strategies. As new traits are developed, new transgenes can be stacked by in planta site-specific integration near previous transgenes, thereby facilitating their introgression to field cultivars as a single segregation locus. However, as each round of integration often requires use of selectable markers, it is more convenient to reuse the selection scheme. The Cre recombinase can be used to delete away previously used selection genes, and other DNA no longer needed after transformation, but the constitutive production of this DNA scanning protein can also affect plant growth. We had previously described in Arabidopsis a split Cre protein fragment complement scheme to reassemble a functional Cre recombinase. As our goal for developing this system was to deploy its use in major crop plants, here we show that Cre protein fragment complementation works in rice with precise recombination structures confirmed by DNA sequencing. As each N-terminal and C-terminal fragment is also flanked by lox recombination sites, they can also self-excise to avoid the need to segregate away the cre DNA. Options to form F1 hybrids homozygous for one transgene, or hemizygous for two different transgenes at the same chromosome location, are discussed.

Performance of F1 progenies developed through crosses between Brassica carinata A. Braun A(♀) and Brassica rapa L (♂)

Performance of F1 progenies developed through crosses between Brassica carinata A. Braun A(♀) and Brassica rapa L (♂)

Insights into acylation mechanisms: co-expression of serine carboxypeptidase-like acyltransferases and their non-catalytic companion paralogs.

SUMMARYSerine carboxypeptidase‐like acyltransferases (SCPL‐ATs) play a vital role in the diversification of plant metabolites. Galloylated flavan‐3‐ols highly accumulate in tea (Camellia sinensis), grape (Vitis vinifera), and persimmon (Diospyros kaki). To date, the biosynthetic mechanism of these compounds remains unknown. Herein, we report that two SCPL‐AT paralogs are involved in galloylation of flavan‐3‐ols: CsSCPL4, which contains the conserved catalytic triad S‐D‐H, and CsSCPL5, which has the alternative triad T‐D‐Y. Integrated data from transgenic plants, recombinant enzymes, and gene mutations showed that CsSCPL4 is a catalytic acyltransferase, while CsSCPL5 is a non‐catalytic companion paralog (NCCP). Co‐expression of CsSCPL4 and CsSCPL5 is likely responsible for the galloylation. Furthermore, pull‐down and co‐immunoprecipitation assays showed that CsSCPL4 and CsSCPL5 interact, increasing protein stability and promoting post‐translational processing. Moreover, phylogenetic analyses revealed that their homologs co‐exist in galloylated flavan‐3‐ol‐ or hydrolyzable tannin‐rich plant species. Enzymatic assays further revealed the necessity of co‐expression of those homologs for acyltransferase activity. Evolution analysis revealed that the mutations of the CsSCPL5 catalytic residues may have taken place about 10 million years ago. These findings show that the co‐expression of SCPL‐ATs and their NCCPs contributes to the acylation of flavan‐3‐ols in the plant kingdom.

Intergenerational Inheritance of Altered Metabolism Phenotypes After Early‐life Stress in Caenorhabditis elegans

Environmental stress experienced during critical periods of animal development has been shown to impact adult phenotypes through changes in behavior or physiology. In humans, undernutrition in utero can lead to obesity and metabolic disorders in adulthood that can be inherited for two generations in the absence of the original stress. However, how particular stresses can result in tissue‐specific changes in target gene expression, and how that gene expression can be inherited, is not well understood. We have established Caenorhabditis elegans nematodes as a model system to investigate the molecular mechanisms that regulate environmental programming of gene expression. C. elegans larvae experiencing early‐life stress (starvation or crowding) may enter the stress resistant, developmentally arrested dauer stage. When environmental conditions improve, larvae will exit dauer and proceed with reproductive development (postdauers, PD). In previous work, we have shown using RNA‐Seq that hermaphrodites that experienced starvation‐induced dauer (PDStv) exhibited significant changes in gene expression compared to continuously fed animals (control, CON), most notably a downregulation of germline‐expressed genes and upregulation of genes with functions in fatty acid metabolism. These changes in gene expression correlated with production of fewer progeny and a decrease in stored intestinal lipids by Oil Red O (ORO) staining in PDStv adults compared to controls. The observed reduction in fecundity in PDStv hermaphrodites was dependent on functional Δ9‐desaturase genes, fat‐5, fat‐6, and fat‐7,as well as the DAF‐12/VDR steroid signaling pathway, indicating a connection between the starvation‐induced metabolism changes and fertility. Interestingly, embryos of PDStv hermaphrodites contained significantly more lipids compared to control embryos, suggesting that PDStv adults prioritize lipid production for reproduction rather than somatic maintenance after dauer exit. We next examined the lipid storage F1 and F2 generation adults using ORO staining, and found that F1 progeny of PDStv adults have significantly increased lipid storage compared to controls. This difference in lipid storage is reset in the F2 generation. Additionally, inheritance of the altered metabolism in F1 adults is dependent upon PRG‐1/PIWI and HRDE‐1/AGO siRNA pathways. In recent work, we are further investigating the connection between metabolism and fecundity of an animal that experienced early‐life stress. We examined the progeny number of PDStv adults that were cultivated on E. coli OP50 supplemented with different fatty acid molecules. We observed that supplementation with oleic acid (OA) resulted in a significant increase in progeny number compared to animals fed only E. coli, while other fatty acids resulted in no change or a decrease in progeny number. Furthermore, the OA‐dependent increase in progeny number required the Δ9‐desaturase FAT‐7, as well as the DAF‐12/VDR steroid signaling pathway, suggesting that OA may be modifying the starvation‐induced phenotypes of PDStv adults. Together, these results suggest that OA may be acting as a signaling molecule to modulate reproductive plasticity through regulation of the DAF‐12/VDR steroid signaling pathway in response to environmental conditions.

MC03g0810, an Important Candidate Gene Controlling Black Seed Coat Color in Bitter Gourd (Momordica spp.).

Seed coat color is one of the most intuitive phenotypes in bitter gourd (Momordica spp.). Although the inheritance of the seed coat color has been reported, the gene responsible for it is still unknown. This study used two sets of parents, representing, respectively, the intersubspecific and intraspecific materials of bitter gourd, and their respective F1 and F2 progenies for genetic analysis and primary mapping of the seed coat color. A large F2:3 population comprising 2,975 seedlings from intraspecific hybridization was used to fine-map the seed coat color gene. The results inferred that a single gene, named McSC1, controlled the seed coat color and that the black color was dominant over the yellow color. The McSC1 locus was mapped to a region with a physical length of ∼7.8 Mb and 42.7 kb on pseudochromosome 3 via bulked segregant analysis with whole-genome resequencing (BSA-seq) and linkage analysis, respectively. Subsequently, the McSC1 locus was further fine-mapped to a 13.2-kb region containing only one candidate gene, MC03g0810, encoding a polyphenol oxidase (PPO). Additionally, the variations of MC03g0810 in the 89 bitter gourd germplasms showed a complete correlation with the seed coat color. Expression and PPO activity analyses showed a positive correlation between the expression level of MC03g0810 and its product PPO and the seed coat color. Therefore, MC03g0810 was proposed as the causal gene of McSC1. Our results provide an important reference for molecular marker-assisted breeding based on the seed coat color and uncover molecular mechanisms of the seed coat color formation in bitter gourd.

COMPARATIVE MORPHOLOGY, BIOSYSTEMATICS, AND REPRODUCTIVE ECOLOGY OF PHACELIA STEBBINSII, P. MARCESCENS, AND P. QUICKII

Phacelia stebbinsii Constance & Heckerd, P. marcescens Eastw. ex J.F.Macbr., and P. quickii J.T.Howell are morphologically similar annual taxa endemic to the west side of the Sierra Nevada in California. Experimental crosses show P. quickii is reproductively isolated from the other two species, and that P. marcescens and P. stebbinsii readily produce fully fertile F1 and S2 hybrid progeny, but typically only when P. marcescens is the carpellate parent. The presence of geographic separation, habitat differences, unilateral crossability, pollen certation, and problems with cotyledon emergence in hybrid seedlings provide evidence P. stebbinsii is distinct from P. marcescens and they are maintained as separate species. Flower and fruit characters used to distinguish these three species from each other appear to be related to differences in seed dispersal and seedling establishment in different habitats.

A single point mutation in a member of FAD2 multigene family resulted in the generation of a high oleic line of Silybum marianum (L.) Gaertn.

Silybum marianum (L.) Gaertn. has been recently valorised as oilseed crop for its productivity and for the chemical composition of its oil. However, a high oleic acid oil (HO) line, which would be useful for cooking but also for biodiesel production and other industrial applications, was not found in its natural germplasm. To address this issue, an ethyl methanesulfonate-induced mutagenesis programme was implemented, and the screening of the mutagenized population led to the identification of a HO mutant line with a much higher oleic acid oil content with respect to the wild type (WT). Since Fatty Acid Desaturase 2 (FAD2) genes are responsible for the determination of oleic acid levels in vegetable oils of other species, the present research focused on the characterization of this gene family as the possible target of mutagenesis. An extremely large multigene family consisting of twenty-one unique and complete FAD2 orthologous sequences was identified in S. marianum. Sequence comparison of all the SmFAD2 genes between the WT and HO genotypes revealed a single nucleotide polymorphism (SNP) in SmFAD2–1, the only fruit-specific gene, resulting in a non-synonymous substitution in the predicted protein in the high oleic genotype. The SNP and the HO phenotype were found to perfectly cosegregate in the F2 progeny derived from the HO x WT crosses, suggesting the direct implication of this gene in the determination of oleic and linoleic acid fruit content in S. marianum fruits.