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Summary: The origin of sweetpotato, a hexaploid species, is poorly understood, partly because the identity of its tetraploid progenitor remains unknown. In this study, we identify, describe and characterize a new species of Ipomoea that is sweetpotato's closest tetraploid relative known to date and probably a direct descendant of its tetraploid progenitor.We integrate morphological, phylogenetic, and genomic analyses of herbarium and germplasm accessions of the hexaploid sweetpotato, its closest known diploid relative Ipomoea trifida, and various tetraploid plants closely related to them from across the American continent.We identify wild autotetraploid plants from Ecuador that are morphologically distinct from Ipomoea batatas and I. trifida, but monophyletic and sister to I. batatas in phylogenetic analysis of nuclear data.We describe this new species as Ipomoea aequatoriensis T. Wells & P. Muñoz sp. nov., distinguish it from hybrid tetraploid material collected in Mexico; and show that it likely played a direct role in the origin of sweetpotato's hexaploid genome. This discovery transforms our understanding of sweetpotato's origin. See also the Commentary on this article by Särkinen et al., 234: 1107–1108. [ABSTRACT FROM AUTHOR]

ABSTRACT Waxy locus introns from 35 accessions of the species comprising the Capsicum annuum complex [C. annuum (7), C. frutescens (10), and C. chinense (11)], C. baccatum (5), C. chacoense [...]

The in trust sweetpotato collection housed by the International Center of Potato (CIP) is one of the largest assemblages of plant material representing the genetic resources of this important staple crop. The collection currently contains almost 6,000 accessions of Ipomoea batatas (cultivated sweetpotato) and over 1,000 accessions of sweetpotato crop wild relatives (CWRs). In this study, the entire cultivated collection (5,979 accessions) was genotyped with a panel of 20 simple sequence repeat (SSR) markers to assess genetic identity, diversity, and population structure. Genotyping and phenotyping of in vitro plantlets and mother plants were conducted simultaneously on 2,711 accessions (45% of the total collection) to identify and correct possible genetic identity errors which could have occurred at any time over the thirty plus years of maintenance in the in vitro collection. Within this group, 533 accessions (19.6%) had errors in identity. Field evaluations of morphological descriptors were carried out to confirm the marker data. A phylogenetic tree was constructed to reveal the intraspecific relationships in the population which uncovered high levels of redundancy in material from Peru and Latin America. These genotypic data were supported by morphological data. Population structure analysis demonstrated support for four ancestral populations with many of the accessions having lower levels of gene flow from the other populations. This was especially true of germplasm derived from Peru, Ecuador, and Africa. The set of 20 SSR markers was subsequently utilized to examine a subset of 189 accessions from the USDA sweetpotato germplasm collection and to identify and reconcile potential errors in the identification of clones shared between these collections. Marker analysis demonstrated that the USDA subset of material had 65 unique accessions that were not found in the larger CIP collection. As far as the authors are aware, this is the first report of genotyping an entire sweetpotato germplasm collection in its entirety. [ABSTRACT FROM AUTHOR]

The triploid genome of plantain (Musa spp., AA group) has been considered intractable to genetic improvement because of the production of putatively homogeneous 2n (= 3x) gametes. Plantain breeding schemes have been based on the hybridization of 2n megaspores from the triploid plantain and haploid microspores from a wild diploid banana. The resultant full-sib populations of tetraploid hybrids exhibited extreme variation in phenotypic characteristics. This study was conducted to analyze the genetic constitution of tetraploid hybrids in order to characterize the nature of the gametes from which they were derived. Parental genotypes were screened with 31 primer pairs specific to different Musa microsatellite loci. Primers which detected polymorphisms between the parental genotypes were used to screen a population of 14 full-sib tetraploid hybrids. A subset of primers was also used to screen a population generated by self-pollination of the parental diploid banana. During analysis of the tetraploid hybrid population, 75% of the alleles donated by the maternal genotype (Obino l'Ewai) were observed to segregate. These data demonstrate the occurrence of recombination during the formation of 2n megaspores in triploid plantain. Analysis of the paternal diploid banana accession (Calcutta 4) and its selfed progeny suggests that this accession is highly heterozygous. These data demonstrate the importance of genetic characterization to Musa breeding, and also indicate that microsatellite markers are well suited for marker-assisted selection systems in Musa., Plantain, a cultivated triploid (2n=3x=33) giant perennial herb, is a natural interspecific hybrid between the two wild species, M. acuminata Colla. and M. balbisiana Colla., which provided the A and [...]

Societal Impact Statement: Crop wild relatives—wild species closely related to cultivated plants—are valuable genetic resources for crop improvement, but gaps in knowledge constrain their conservation and limit their further use. We develop new information on the distributions, potential breeding value, and conservation status of the 16 known wild relatives of cultivated pumpkins, squashes, zucchini, and gourds (Cucurbita L.). The taxa occur from the central USA to Central America, plus two South American species, with the greatest richness in central Mexico and the western borderlands between Mexico and the USA. We determine the majority of species are of medium priority for conservation, both with regard to collecting for ex situ maintenance, and for enhanced habitat protection. SummaryCrop wild relatives are valuable genetic resources for crop improvement. Knowledge gaps, including with regard to taxonomy, distributions, and characterization for traits of interest constrain their use in plant breeding. These deficiencies also affect conservation planning, both with regard to in situ habitat protection, and further collection of novel diversity for ex situ maintenance.Here we model the potential ranges of all 16 known wild cucurbit taxa (Cucurbita L.), use ecogeographic information to infer their potential adaptations to abiotic stresses, and assess their ex situ and in situ conservation status.The taxa occur from the central USA to Central America, plus two South American species. Predicted taxon richness was highest in central Mexico and in the western borderlands between Mexico and the USA. We find substantial ecogeographic variation both across taxa and among populations within taxa, with regard to low temperatures, high and low precipitation, and other adaptations of potential interest for crop breeding.We categorize 13 of the taxa medium priority for further conservation as a combination of the ex situ and in situ assessments, two low priority, and one sufficiently conserved. Further action across the distributions of the taxa, with emphasis on taxonomic richness hotspots, is needed to comprehensively conserve wild Cucurbita populations. [ABSTRACT FROM AUTHOR]

Members of the highly polyphagous Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) species complex cause major crop damage by feeding and by transmitting plant viruses. The Middle East-Asia Minor 1 (MEAM1) of the B. tabaci complex is by far the most problematic whitefly affecting crops including cultivated watermelon (Citrullus lanatus ; Cucurbitaceae: Cucurbitales). Watermelon cultivars share a narrow genetic base and are highly susceptible to whiteflies. We studied the potential of C. ecirrhosus , a perennial desert species that can be hybridized with C. lanatus , as a source of whitefly resistance for cultivated watermelon. The results of this study indicate that C. ecirrhosus offers resistance (although not total) against the MEAM1 B. tabaci based on, at least, antibiosis and antixenosis. Whitefly performance concerning developmental survival, body size attainment, and nonpreference were suppressed on C. ecirrhosus compared with the watermelon cultivar 'Sugar Baby'. Also, our olfactometer results indicated that the adults were less attracted to leaf volatiles of C. ecirrhosus. Although there is a pungent odor associated with the leaves of C. ecirrhosus , the leaf volatiles had no toxic effect on adult whitefly survival as compared with cultivated watermelon. We also demonstrated that plants of C. ecirrhosus can be clonally propagated from vine cuttings of the parent plant. Using traditional breeding procedures, C. ecirrhosus was hybridized with C. lanatus and viable F1 and F2 seeds were produced. This is the first report of pest resistance in C. ecirrhosus. This wild species offers a source of resistance against whiteflies for the improvement of cultivated watermelon. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas) plays a critical role in food security and is the most important root crop worldwide following potatoes and cassava. In the United States (US), it is valued at over $700 million USD. There are two sweetpotato germplasm collections (Plant Genetic Resources Conservation Unit and US Vegetable Laboratory) maintained by the USDA, ARS for sweetpotato crop improvement. To date, no genome-wide assessment of genetic diversity within these collections has been reported in the published literature. In our study, population structure and genetic diversity of 417 USDA sweetpotato accessions originating from 8 broad geographical regions (Africa, Australia, Caribbean, Central America, Far East, North America, Pacific Islands, and South America) were determined using single nucleotide polymorphisms (SNPs) identified with a genotyping-by-sequencing (GBS) protocol, GBSpoly, optimized for highly heterozygous and polyploid species. Population structure using Bayesian clustering analyses (STRUCTURE) with 32,784 segregating SNPs grouped the accessions into four genetic groups and indicated a high degree of mixed ancestry. A neighbor-joining cladogram and principal components analysis based on a pairwise genetic distance matrix of the accessions supported the population structure analysis. Pairwise F ST values between broad geographical regions based on the origin of accessions ranged from 0.017 (Far East – Pacific Islands) to 0.110 (Australia – South America) and supported the clustering of accessions based on genetic distance. The markers developed for use with this collection of accessions provide an important genomic resource for the sweetpotato community, and contribute to our understanding of the genetic diversity present within the US sweetpotato collection and the species. [ABSTRACT FROM AUTHOR]

The United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Plant Genetic Resources Conservation Unit in Griffin, GA maintains the United States germplasm collection for Ipomoea spp. (Convolvulaceae). During 2012-2014, 737 sweetpotato, Ipomoea batatas (L.) Lam., plant introductions (PI) were acquired as tissue-culture plantlets and then acclimated to greenhouse conditions at the USDA, ARS, U. S. Vegetable Laboratory (USVL), Charleston, SC. Single plants were transferred to plastic-covered plant beds to produce cuttings for replicated field trials. Storage roots were harvested from 690 PIs grown in the field and 695 PIs grown in pots. Color coordinates were obtained for each PI using a tristimulus colorimeter. Hue angle values (h*) ranged from 8.2° to 88.3° (x¯ = 54.9°) for the periderm (peel or skin) of field-grown storage roots (n = 690 PIs) and − 9.4° (= 350.6°) to 96.2° (x¯ = 51.3°) for pot-grown roots (n = 695 PIs). The red-green coordinate (a*) ranged from 0.8 to 30.7 (x¯ = 12.8) for the periderm of field-grown roots and − 2.0 to 44.9 (x¯ = 16.1) for pot-grown roots. The yellow-blue coordinate (b*) ranged from 2.8 to 33.1 (x¯ = 19.4) for the periderm of field-grown roots and − 7.4 to 38.1 (x¯ = 19.3) for pot-grown roots. Color saturation (chroma, C*) ranged from 13.7 to 35.8 (x¯ = 24.9) for the periderm of field-grown roots and 14.9-45.5 (x¯ = 29.3) for pot-grown roots. Lightness (white-black, L*) ranged from 32.6 to 81.7 (x¯ = 54.6) for the periderm of field-grown roots and 32.1-88.2 (x¯ = 64.0) for pot-grown roots. Hue angles ranged from − 13.1° (= 346.9°) to 100.9° (x¯ = 80.9°) for the stele (flesh) of field-grown storage roots (n = 672 PIs) and − 29.9° to 103.5° (x¯ = 81.6°) for pot-grown roots (n = 676 PIs); a* ranged from − 5.6 to 35.0 (x¯ = 8.0) for the stele of field-grown roots and − 6.0 to 41.0 (x¯ = 7.6) for pot-grown roots; and b* ranged from − 7.7 to 56.1 (x¯ = 34.6) for the stele of field-grown roots and − 12.6 to 56.1 (x¯ = 31.8) for pot-grown roots. C* ranged from 12.7 to 65.8 (x¯ = 37.2) for the stele of field-grown roots and 8.9-65.7 (x¯ = 34.5) for pot-grown roots; and L* ranged from 27.8 to 91.1 (x¯ = 77.7) for the stele of field-grown roots and 28.2-91.9 (x¯ = 80.4) for pot-grown roots. There were significant relationships between stele color (h*) and percent dry matter, with orange stele having a significantly lower % dry matter (x¯ = 25.6%, n = 183) compared with roots with cream/white stele (x¯ = 30.8%, n = 373). There appears to be wide genetic diversity for root color characteristics for the United States sweetpotato germplasm collection. [ABSTRACT FROM AUTHOR]

Scanning electron and light microscopy were used to examine pollen of the currently recognized species (and forms) within the genus Citrullus (Cucurbitaceae). Materials examined included: C. lanatus (Thunb.) Matsum. & Nakai, the citron (C. amarus Schrad.), the egusi [C. mucosospermus (Fursa) Fursa], C. colocynthis (L.) Schrad., C. rehmii De Winter, C. ecirrhosus Cogn., and the gemsbok cucumber [C. naudinianus (Sond.) Hook. f.]- also referred to in the literature as Acanthosicyos naudinianus (Sond.) C. Jeffrey. Pollen of all species were similar in shape differing slightly in their polar (P) and equatorial (E) axes and P/E. In general, all were characterized as prolate and tricolpate with a small polar area and reticulate ornamentation. Flow cytometry revealed C values for the taxa examined as ranging from 0.8 to 1.04 pg DNA per 2C nuclei. A mutant affecting pollen ornamentation was identified in PI 482261, a C. amarus citron from Zimbabwe. Pollen ornamentation on PI 482261 was rugulate. An examination of 15 additional accessions from neighboring areas in Zimbabwe revealed a second rugulate type in PI 482312, while the remaining 14 C. amarus accessions were reticulate. Successful hybridizations were made between C. colocynthis (PI 652554) and C. naudinianus (GRIF 14032), and between C. rehmii (PI 670011) and C. naudinianus (GRIF 14032). The F1 hybrids of both crosses were extremely vigorous and exhibited some characteristics (i.e., branching and storage root formation) associated with the male parent. Other characteristics such as tendril length and shape, and leaf size and shape, were intermediate between the parents. To date, the interspecific F1 hybrids have produced only shrunken (nonviable) pollen. [ABSTRACT FROM AUTHOR]

Crop wild relatives of sweetpotato [Ipomoea batatas (L.) Lam., I. series Batatas] have the potential to contribute to breeding objectives for this important root crop. Uncertainty in regard to species boundaries and their phylogenetic relationships, the limited availability of germplasm with which to perform crosses, and the difficulty of introgression of genes from wild species has constrained their utilization. Here, we compile geographic occurrence data on relevant sweetpotato wild relatives and produce potential distribution models for the species. We then assess the comprehensiveness of ex situ germplasm collections, contextualize these results with research and breeding priorities, and use ecogeographic information to identify species with the potential to contribute desirable agronomic traits. The fourteen species that are considered the closest wild relatives of sweetpotato generally occur from the central United States to Argentina, with richness concentrated in Mesoamerica and in the extreme Southeastern United States. Currently designated species differ among themselves and in comparison to the crop in their adaptations to temperature, precipitation, and edaphic characteristics and most species also show considerable intraspecific variation. With 79% of species identified as high priority for further collecting, we find that these crop genetic resources are highly under-represented in ex situ conservation systems and thus their availability to breeders and researchers is inadequate. We prioritize taxa and specific geographic locations for further collecting in order to improve the completeness of germplasm collections. In concert with enhanced conservation of sweetpotato wild relatives, further taxonomic research, characterization and evaluation of germplasm, and improving the techniques to overcome barriers to introgression with wild species are needed in order to mobilize these genetic resources for crop breeding. [ABSTRACT FROM AUTHOR]

Various methods to synthesize capsinoids (the nonpungent analogs of capsaicinoids) from precursor molecules have been reported. Capsinoids are also naturally present, at typically low concentrations, in the fruit of many Capsicum species and genotypes. However, they are also present in the fruit of select genotypes at high concentrations. The fruit of high-capsiate genotypes represents a commercial source of these compounds. To date, no method has been published that efficiently extracts and purifies capsinoids from Capsicum fruit in a rapid and simple bulk process. This study evaluated the efficacy of various organic solvents for the extraction of capsinoids from dried Capsicum annuum fruit. Among the organic solvents evaluated, pentane appeared to provide a good combination of both recovery and purity. A subsequent liquid/liquid extraction step, utilizing pentane and acetonitrile, resulted in 26.3% (wt/wt) capsiate and 19.4% (wt/wt) dihydrocapsiate for a combined capsinoids yield of 45.7% (wt/wt). A third step, involving a rapid hp20ss chromatography column using a water/acetonitrile gradient, resulted in a combined capsinoids yield of 96.6% (wt/wt). [ABSTRACT FROM AUTHOR]

Data on intra-specific variability for seed oil content, physical characteristics and fatty acid composition in Cucurbita moschata and Cucurbita argyrosperma are lacking in the scientific literature. We examined 528 genebank accessions of C. moschata and 166 accessions of C. argyrosperma – which included members of both subsp. argyrosperma and subsp. sororia – for seed oil content, oil physical characteristics and fatty acid composition. The oil of both species had near-identical viscosities, viscosity indices, colour and oxidative stabilities while the oil of C. argyrosperma had a slightly higher pour point, cloud point, percentage of free fatty acids and acid value when compared with C. moschata. Mean oil content values of the two species were similar at 28.7 ± /2.7 and 29.8 ± /2.6% for C. moschata and C. argyrosperma, respectively. The mean seed oil content of C. argyrosperma subsp. argyrosperma var. palmeri (32.1%) was significantly higher than that of the other taxa examined. The average (mean) percentage of total seed weight attributable to the kernel was 77.2% in C. moschata (n= 34) and 74.5% in C. argyrosperma (n= 46). The percentage of total seed weight attributable to the hull was correlated with seed oil content, in both species. Linoleic was the predominant fatty acid in all the samples analysed. Means for individual fatty acids in C. moschata were linoleic 48.5%, oleic 22.6%, palmitic 20.7% and stearic 7.5%. Means for individual fatty acids in C. argyrosperma were linoleic 47.3%, oleic 27.5%, palmitic 16.5% and stearic 8.0%. [ABSTRACT FROM AUTHOR]

Highlights: [•] Seed oil content among nine Capsicum species ranged from 10.8% to 35.9%. [•] Linoleic acid was the predominant fatty acid in all samples. [•] Seed composition of the wild taxa was similar to that of the cultivated species. [Copyright &y& Elsevier]

Mature fruit of 330 accessions of Capsicum chinense Jacq. from the USDA/ARS Capsicum germplasm collection were characterized for fruit length, width, weight, and color. Mean fruit length was determined to be 47 mm with a range from 7.9 mm to 113.7 mm. Mean fruit width was 21.17 mm with a range of 6.18 mm to 40.0 mm. Mean fruit weight was 6.31 g with a range of 0.18 g to 22.7 g. Distributions of all characteristics were positively skewed. Distributions of fruit length, fruit weight, and fruit length/width failed the Kolmogorov-Smirnov test for normality. The distribution for fruit width was normal. Ninety-two percent of the accessions examined were elongate. Mature fruit colors included red, orange, yellow, brown (chocolate), and cream. The germplasm collection contained primarily pendent larger-fruited cultivated forms of the species, but also contained upright small-fruited primitive and semipendent transitional forms. These data define the variability for mature fruit characteristics within this germplasm collection and provide a baseline against which future introductions/acquisitions can be compared. Additional sampling of the gene pool might be expected to substantially enhance the genetic variability within the primitive forms of this species. [ABSTRACT FROM AUTHOR]

Fruit of 40 genotypes of Capsicum frutescens L. from the US Department of Agriculture/Agricultural Research Service Capsicum germplasm collection were analyzed for a variety of fruit quality parameters, including fruit size, weight, and concentrations of capsaicinoids, sucrose, glucose, fructose, malic acid, and total acid equivalents. Fruit weight ranged from 0.23 g fresh weight to 4.04 g fresh weight (average 1.05g). Fruit length/width ranged from 1 to 8.0 (average, 3.61). Capsaicin concentrations ranged from 34 to 350 mg·100 g-1 fresh weight (average, 135 mg·100 g-1 fresh weight). Sucrose concentrations ranged from 0.28 to 1.0 g·100 g-1 (average, 0.6 g·100 g-1 fresh weight). Total sugar extracts ranged from 0.73% to 2.6% (average, 1.55%). Malic acid concentrations and total acid equivalents ranged from 0.62 to 2.29 g·100 g-1 fresh weight (average, 2.07 g·100 g-1 fresh weight) and 0.97 to 3.31 g·100 g-1 (average, 1.87 g·100 g-1) respectively. These data demonstrate an approximate 4 to 14-fold range in values for the characteristics examined, suggesting the presence of sufficient variability for these traits within this species to support the development of germplasm enhanced for specific or multiple fruit quality attributes. [ABSTRACT FROM AUTHOR]

We report a case of angioimmunoblastic T-cell lymphoma in a patient who presented with the typical clinical features of generalized lymphadenopathy: bilateral pleural effusions, splenomegaly, ascites, and polyclonal hypergammaglobulinemia. Angioimmunoblastic T-cell lymphoma is one of the more specific peripheral T-cell lymphomas accounting for approximately 15% to 20% of cases and approximately 1% to 2% of all non-Hodgkin lymphomas. Involved lymph nodes reveal partial effacement of normal architecture by a polymorphic infiltrate composed of small-to-intermediate-sized lymphocytes, plasma cells, eosinophils, and histiocytes with prominent proliferation of high endothelial venules and follicular dendritic cells. Neoplastic T cells are small to intermediate in size, show abundant clear cytoplasm with distinct membranes, are predominantly CD4 positive, and often show aberrant coexpression of CD10. The clinical course is aggressive, with a median survival of less than 3 years. Most patients succumb to infectious complications rather than tumor burden, making the administration of aggressive chemotherapy difficult. [ABSTRACT FROM AUTHOR]

Xylella fastidiosacauses many important plant diseases including Pierce’s disease (PD) in grape and almond leaf scorch disease (ALSD). DNA-based methodologies, such as randomly amplified polymorphic DNA (RAPD) analysis, have been playing key roles in genetic information collection of the bacterium. This study further analyzed the nucleotide sequences of selected RAPDs fromX. fastidiosastrains in conjunction with the available genome sequence databases and unveiled several previously unknown novel genetic traits. These include a sequence highly similar to those in the phage family of Podoviridae. Genome comparisons amongX. fastidiosastrains suggested that the “phage” is currently active. Two other RAPDs were also related to horizontal gene transfer: one was part of a broadly distributed cryptic plasmid and the other was associated with conjugal transfer. One RAPD inferred a genomic rearrangement event amongX. fastidiosaPD strains and another identified a single nucleotide polymorphism of evolutionary value. [ABSTRACT FROM AUTHOR]

An enzyme immunoassay was evaluated for its ability to quantify total capsaicinoids in fruit of 16 genotypes representing four species of Capsicum, in comparison with high-performance liquid chromatography (HPLC). Concentrations of capsaicinoids in samples ranged from 5.1 to 4284 ppm, and from 0.6 to 3467 ppm, as determined by enzyme immunoassay (EIA) and HPLC, respectively. Lowest concentrations of capsaicinoids occurred in sweet bell and pimento types (C. annuum L.), and the highest concentration occurred in a small-fruited ‘bird’-type accession of C. frutescens L. (PI 593924). Estimates of capsaicinoids obtained by EIA and HPLC were highly correlated (R2=0.996). Data suggest that EIA is an effective means for estimating total capsaicinoids in extracts of fresh chile fruits. [Copyright &y& Elsevier]

Discs of cortical and perimedullary tissue from tubers of potato (Solanum tuberosum L. cv. Superior) formed adventitious shoots when cultured on a medium containing Murashige and Skoog's salts, myo-inositol, 100 mg/l; folic acid, 0.5 mg/l: D-biotin, (0.05 mg/l; gibberellic acid (GA3), 0.5 mg/l; thiamine HCl, 0.1 mg/l; glycine, 2.0 mg/l; pyridoxine HCl, 0.5 mg/l; nicotinic acid, 0.5 mg/l; sucrose, 25 g/l; casein hydrolysate, 1 g/l Bacto agar, 9.0 g/l; and a cytokinin [N6-benzylaminopurine (BAP), N6-γ,γ-dimethylallylaminopurine (2iP), or N6-furfurylaminopurine (kinetin)]. Discs of pith tissue either failed to survive or produced callus but did not undergo morphogenesis. Cytokinin was essential for explant survival, while BAP at 3.0 mg/l was most efficacious in promoting shoot initiation. Auxin was not essential for shoot initiation or development; however, a low concentration (0.03 mg/l) of α-naphthaleneacetic acid (NAA) stimulated both explant survival and the number of shoots produced per disc. Indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA) did not stimulate shoot initiation. GA3 was essential for both shoot initiation and subsequent shoot development. The highest incidence of morphogenesis (over 100 shoots in 12 weeks) occurred from tuber discs cultured at 18°C constant and under a photon flux density of 60 μE m-2s-1. No difference in regenerative ability was found in explants taken from source tubers stored for 0 to 20 weeks at 4°C. A histological examination indicated that shoots developed from small clusters of meristematic cells which were initiated from within small protuberances on the surface of the tuber disc 3 weeks after transfer. [ABSTRACT FROM AUTHOR]

Astragalus L. is one of the largest angiosperm complex genera that belongs to the family Fabaceae, subfamily Papilionoideae or Faboideae under the subtribe Astragalinae of the tribe Galegeae. The current study includes the whole plant morphology, DNA barcode (ITS2), and molecular marker (SCoT). Ten taxa representing four species of Astragalus were collected from different localities in Egypt during the period from February 2018 to May 2019. Morphologically, identification and classification of collected Astragalus plants occurred by utilizing the light microscope, regarding the taxonomic revisions of the reference collected Astragalus specimens in other Egyptian Herbaria. For molecular validation, ten SCoT primers were used in this study, producing a unique banding pattern to differentiate between ten samples of Astragalus taxa which generated 212 DNA fragments with an average of 12.2 bands per 10 Astragalus samples, with 8 to 37 fragments per primer. The 212 fragments amplified were distributed as 2 monomorphic bands, 27 polymorphic without unique bands, 183 unique bands (210 Polymorphic with unique bands), and ITS2 gene sequence was showed as the optimal barcode for identifying Astragalus L. using BLAST searched on NCBI database, and afterward, analyzing the chromatogram for ITS region, 10 samples have been identified as two samples representing A. hauarensis, four samples representing A. sieberi, three samples representing A. spinosus and one sample representing A. vogelii. Based on the ITS barcode, A. hauarensis RMG1, A. hauarensis RMG2, A. sieberi RMG1, A. sieberi RMG2, A. sieberi RMG3, A. sieberi RMG4, A. spinosus RMG1, A. spinosus RMG2, A. spinosus RMG3, A. vogelii RMG were deposited into GenBank with accession # MT367587.1, MT367591.1, MT367593.1, MT367585.1, MT367586.1, MT367588.1, MT160347.1, MT367590.1, MT367589.1, MT367592.1, respectively. These results indicated the efficiency of SCoT markers and ITS2 region in identifying and determining genetic relationships between Astragalus species. [ABSTRACT FROM AUTHOR]

Mature fruit of 295 accessions of Capsicum baccatum from the USDA/ARS Capsicunt germplasm collection were characterized for fruit length, width, weight, and color. Mean fruit weight was determined to be 5.91 g with a range of 0.15 to 22.8 g. Mean fruit length was 6.01 cm with a range of 0.8 to 16.0 cm. Mean fruit width was 1.86 cm and a range of 0.5 to 4.75 cm. Distributions of all characteristics were positively skewed and failed the Kolmogorov-Smirnov test for normality. The distribution of fruit weight values was the most highly skewed, possibly reflecting a more intense human selection pressure for this characteristic. Distributions of fruit width, length, weight, and length:width were leptokurtic (long-tailed). Ninety-three percent of accessions were elongate. Mature fruit colors included red (73.6%), orange (19.7%), yellow (3%), green (0.3%), and mixed (3%). These data suggest that variability for mature fruit characteristics within this germplasm collection is considerable and that variability for fruit length, width, weight, and color is sufficient to provide the basis for the improvement of the aji crop. [ABSTRACT FROM AUTHOR]