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Solanum incanum, the wild ancestor of eggplant, Solanum melongena, has been considered as a source of variation for high content of phenolic acid conjugates in breeding programmes aimed at improving the functional quality of eggplant. We have evaluated the morphological and phenolic acids content in an interspecific family including S. incanum ( P1), S. melongena ( P2), their interspecific hybrid ( F1), progeny from the selfing of the F1 ( F2) and the backcross of the F1 to P2 ( BC1P2). Many morphological differences were found between parents, while the F1 was intermediate for most traits. However, F1 plants were taller and pricklier and presented higher fruit flesh browning than any of the parents. F2 and BC1P2 were morphologically highly variable and the results obtained suggest that a rapid recovery of the characteristic combination of S. melongena traits can be achieved in a few backcross generations. Segregation for prickliness was found to be compatible with simple genetic control, prickliness being dominant over non-prickliness. A total of 16 phenolic acid conjugates were studied, of which chlorogenic acid (5- O-( E)-caffeoylquinic acid) was the most common compound in all samples, averaging 77.8% of all hydroxycinnamic acid derivatives. Contents of total phenolic acid conjugates were much higher in S. incanum than in S. melongena fruit flesh, and no major differences were found in the profile of phenolic acids among parents. The interspecific hybrid ( F1) was intermediate between the two parents in phenolic acids content. Non-segregating generations presented considerable variation in phenolic acids content, but the range of variation was wider in segregating F2 and BC1P2 generations. Additive genetic effects were the most important in explaining the results obtained for the phenolic acids content. A number of BC1P2 plants presented a good combination of phenolic acids content and fruit weight or flesh browning. Overall, the results demonstrate that improvement of functional quality in S. melongena can be obtained using S. incanum as a donor of alleles for high phenolic acids content. [ABSTRACT FROM AUTHOR]

Eggplant (Solanum melongena) is amenable to grafting and this technique can be exploited to improve production of this vegetable crop. Here, we study the performance of the 'Crista! F l ' eggplant cultivar grafted onto a total of 1 7 rootstocks, including five families, each o f which is made by two parents and their hybrid, as well a commercial eggplant rootstock and a self-grafted control. Three families consist of eggplant rootstocks, including a S. melongena intraspecific family and two interspecific families of S. melongena with S. incanum and S. aethiopicum. Two other families are made of interspecific hybrids between tomato (S. lycopersicum) and S. habrochaites. Overall, eggplant rootstocks showed a good compatibility and graft success, while tomato rootstocks had a poor compatibil ity and only S. habrochaites rootstocks could be evaluated for yield and fruit production. Important differences were found for susceptibility to nematodes, with some S. melongena accessions showing the best results. Eggplant hybrids were intermediate to their parents in nematode resistance and tomato rootstocks proved to be very susceptible to nematodes. Yield, fruit number and earliness were higher in the most vigorous rootstocks, in particular in the S. melongena x S. aethiopicum hybrid. Good performance was also observed for some S. melongena accessions, but poor results were obtained when using S. incanum, S. aethiopicum and S. habrochaites rootstocks. Some differences were observed for fruit size and shape among the different rootstocks, but for the best rootstocks no differences of commercial relevance were apparent. The results suggest that S. melongena germplasm and both intraspecific and interspecific eggplant hybrids seem to be promising materials for developing new rootstocks for eggplant production. [ABSTRACT FROM AUTHOR]

Ají ( Capsicum baccatum L.) and rocoto ( C. pubescens R. & P.) are two Capsicum pepper species native to the Andean region that have not been subjected to intensive breeding. However, the increase in its demand in European markets has sparked the development of breeding programmes for adaptation to Mediterranean climates, which include breeding for higher levels of bioactive compounds. We have studied the composition of red and yellow carotenoids ( CR and CY, respectively), ascorbic acid (AA), and total phenolics (TP) in 34 accessions of Capsicum, including 23 of C. baccatum, eight of C. pubescens, and 3 controls of C. annuum, which were grown in Spain both under greenhouse (GH) and open field (OF) conditions. The results show that in both growing conditions C. baccatum presents a considerable variation for most of the traits studied, with several accessions having similar or higher levels than C. annuum for the compounds studied. This indicates that C. baccatum is an important source of antioxidant compounds with nutritional value. On the contrary, C. pubescens had a poor performance, with low levels for all the compounds studied, and a poor adaptation to the conditions of Mediterranean climates. When considering the GH or OF growing cycles separately, heritability values were high (>0.75) for CR, CY and AA, and moderate (0.42 for GH and 0.62 for OF) for TP. The existence of an important genotype × environment interaction resulted in lower levels for heritability when considering both growing cycles together, although the values were still high for CR and AA (>0.6). Positive significant genotypic correlations among all the traits studied were found, except for TP with CR and AA in the OF cycle. This information indicates that there are good prospects for developing C. baccatum varieties with higher levels of bioactive compounds. [ABSTRACT FROM AUTHOR]

Black-coloured eggplants ( Solanum melongena) represent the commercially most important group of eggplants in Europe and North America. Most of the modern varieties of black eggplants correspond to F1 hybrids, which at the same time constitute an elite gene pool for the development of new varieties. However, there are many black landraces and old varieties, which could be useful as sources of variation for black eggplant breeding programmes as well as for the broadening of the genetic diversity of the breeders’ gene pool. We have studied the morphological and molecular [amplified fragment length polymorphism and simple sequence repeat (SSR)] diversity in a collection of 38 black eggplant accessions, including commercial (modern F1 hybrid and old nonhybrid) varieties and landraces as well as in six nonblack control eggplants, from different origins. The results show that black eggplants contain a considerable morphological and molecular diversity, but commercial varieties, and in particular F1 hybrids, display a reduced morphological and molecular diversity when compared with landraces. The principal components analysis morphological and principal coordinates analysis molecular analyses show that commercial F1 hybrids group together, indicating that they share a common and narrow gene pool. Commercial F1 hybrids present a series of productive advantages, like early production, intense black colour (low L*, a* and b*) values and absence of fruit calyx prickles. However, several of the landraces and old nonhybrid varieties studied present a high yield as well as other traits of interest for eggplant breeding. Furthermore, given the low genetic diversity of F1 hybrids and the moderate level of SSR heterozygosity found in these materials (0.382), introduction of black landraces and old varieties in the present breeding programmes could contribute to broadening the gene pool used by breeders and this could help increase the heterosis for yield of F1 hybrids, which is greatly favoured by high heterozygosity levels. [ABSTRACT FROM AUTHOR]

Spanish striped eggplants ( Solanum melongena L.) are generally known as Listada. Among them, the most internationally renowned is the Listada de Gandía heirloom. Enhancement and legal protection of these local materials requires the analysis of their characteristics, diversity and relationships with similar accessions. We performed a morphological, agronomic and molecular (amplified fragment length polymorphism; AFLP) characterization of 33 eggplant accessions, which included 20 Striped accessions, of which nine were Spanish (five Listada de Gandía and four of Other Spanish Listada), 11 non-Spanish (six of Non-Spanish Listada and five of Other Non-Spanish Striped) and 13 Non-Striped accessions. The Striped accessions presented a range of morphological, agronomic and genetic diversity comparable to the one observed in the Non-Striped accessions. Multivariate PCA (morphological) and PCoA (molecular) analyzes group together the Listada accessions, and clearly separate the three Listada subgroups ( Listada de Gandía, Other Spanish Listada and Non-Spanish Listada). On the other hand, the Other Non-Spanish Striped accessions are closer to Non-Striped than to Listada accessions. Listada eggplants, as well as each of their subgroups, are characterized by a syndrome of morphological traits that allows distinguishing them from other accessions. Furthermore, AFLP markers which allow distinguishing Listada accessions and the Listada de Gandía heirloom have been found. The agronomic characterization shows that despite the low diversity within Listada de Gandía group, it is possible to select accessions with improved agronomic performance. The results obtained have important implications for the conservation, improvement and legal protection of Spanish striped eggplants, and in particular of the Listada de Gandía heirloom. The methodology and approaches used may provide a model for the enhancement and protection of other vegetable crops heirlooms. [ABSTRACT FROM AUTHOR]

The article studies 10 species of Solanum section Basarthrum using amplified fragment length polymorphisms. Two distinct molecular elements were identified, one autogamous, the other self incompatible, that mimic a species pair of wild tomatoes native to the same region of Peru. The Caripensia proved to be the most diverse genetically, allowing morphologically similar species to be distinguished.

Narrow intraspecific variation for sugar content in pepino ( Solanum muricatum Aiton) hinders the development of new pepino cultivars with improved fruit quality. However, some wild related species have high soluble solids concentration (SSC) and titratable acidity (TA). Generation means analysis was used to estimate genetic parameters for SSC, TA and ascorbic acid concentration (AAC) in two families of interspecific crosses between a S. muricatum parent (Sm-32) and one accession of each of the wild species Solanum caripense (Sc-4) and Solanum tabanoense (St-1). In both families, the additive effect [d] was the only significant parameter for SSC, the alleles of wild species contributing positively to increasing SSC values. For TA, genetic effects associated with additivity [d] and dominance [h] were detected in both families. Additionally, in Sm-32 × Sc-4 nonallelic interactions associated with dominance ([j] and [l]) were significant. For this trait, alleles from the wild species contribute additively to a high value of the character, but are recessive to those of the cultivated S. muricatum. No genetic variation was found for AAC. Broad-sense heritabilities for SSC and TA were intermediate (0.40 to 0.50). Positive significant genetic correlations (around 0.68 in both families) were found between SSC and TA. The results obtained in backcrosses of interspecific hybrids to S. muricatum, together with the estimates of genetic advance after selection, indicate that recovery of individuals with higher SSC and TA and adequate SSC/TA ratio can be achieved in a few backcrosses. In conclusion, this work indicates that wild species S. caripense and S. tabanoense are worthy sources of variation for improving pepino fruit quality. [ABSTRACT FROM AUTHOR]

Pepino mosaic virus (PepMV), a potexvirus first described in 1980 from pepino (Solanum muricatum) plants cultivated in Peru, was isolated from diseased tomato plants in the Netherlands in 1999, and is now the cause of an emerging tomato disease in Europe. In a survey of central and southern Peru, 65 wild and four cultivated populations of Lycopersicon, as well as six populations of other species of Solanaceae, were tested for the presence of PepMV and six other viruses. Of the Lycopersicon population sampled, 23 (35.4%) reacted positively in double antibody sandwich (DAS)-enzymelinked immunosorbent assay (ELISA) with antisera to PepMV. DAS-ELISA tests for PepMV of other solanaceous species were negative, except for one sample of pepino (Solanum muricatum). Mechanical inoculation of susceptible Lycopersicon esculentum cv. NE-1 plants with crude sap extracts of 20 of these samples confirmed that 15 of them (from the Departments of Apurimac, Arequipa and Moquegua) were infected with PepMV; these inoculated plants were also DAS-ELISA positive and, in most cases, developed symptoms. Thirteen of the infective extracts were obtained from plants of wild Lycopersicon species (three L. chilense, three L. chmielewskii, two L. parviflorum and five L. peruvianum) and one each from the cultivated species L. esculentum and S. muricatum. The wild Lycopersicon species are newly reported natural hosts of PepMV. Tests for the other six viruses were negative, except that two samples contained Tomato mosaic virus. Thus, PepMV occurs in Lycopersicon species in central and southern Peru, even in isolated wild populations. These results indicate that the virus is not new to the region and has an efficient mechanism of natural transmission. [ABSTRACT FROM AUTHOR]

Lophophora williamsii is an ornamental slow growth cactus highly appreciated by cacti growers and hobbyists. Its demand is often satisfied through illegal collection of wild plants and many populations are threatened with extinction. Thus, an efficient in vitro protocol without plant growth regulators will be of great interest for conservation purposes of this cactus. Eight different germination media, combining Murashige and Skoog medium (MS, full and half-strength), sucrose (20 and 30 g L −1 ) and agar (8 and 10 g L −1 ), were used to study germination rate, number of seedlings with areoles and initial seedling development. Germination rates among culture media only differed significantly in the first 14 days after sowing (DAS), reaching 67–75% at the end of the assay (49 DAS). Remarkable interactions among media components were detected, and 20 g L −1 sucrose and 8 g L −1 agar combination gave the highest performance for both size and number of areoles. Following germination assay, a growth assay was conducted during 105 days using three growth media (GrM) at different sucrose concentration (15, 30 and 45 g L −1 ) to evaluate the increase in seedling size and number of areoles. Regardless of their initial size, 15 g L −1 sucrose provided the best results for both traits. Size increase was higher in the 4–5 mm seedling group, while increase in areoles was greater in 2-3 mm seedlings. It was possible to develop an in vitro protocol, in absence of plant growth regulators, which allows maximizing L. williamsii germination and growth during its first stages of development, which may increase the availability of plants in the market and avoid exhaustion of wild populations. Furthermore, plants grown ex situ could be reintroduced in endangered natural populations. [ABSTRACT FROM AUTHOR]

Abstract Spectral Solar Photosynthetically Photon Flux Density (PPFD) (380 to 780 nm) reaching the surface of a plant in different lighting conditions has been analyzed in order to better understand the different photosynthetic performance of plants depending on their spatial situation and the vegetation surrounding. A comparison between the shadow of several trees in a sunny day and the case of a cloudy day in an open space has been studied. Three isolated trees (a palm tree, an olive tree and a shrub oleander) and a tipuana grove have been studied. The study has been developed in Valencia (Spain) during January and February 2017. A portable Asensetek Standard ALP-01 spectrometer with a measurement wavelength range of 380 to 780 nm, has been used. Conditions with higher PPFD received are found to be, apart from those of a sunny day, those for cloudy day (with a spectral maximum in the Green region of the spectrum), and those for individual trees and shrub shadows in a sunny day (with a spectral maximum in the Blue region). The case in which less amount of PPFD is received is that under the shadow of tipuana grove (with a spectral maximum in the Infrared region of the spectrum). In fact the order of magnitude in which the PPFD in a cloudy day exceeds the PPFD under the tipuana grove shade is up to 20. Highlights • Different light conditions affect photosynthesis plants performance. • Cloudy day is compared with shadows in sunny day. • Shadow under isolated trees (palm tree, olive tree and shrub oleander) is compared with grove one (tipuana). • Diffuse radiation is found to be higher on cloudy day than under tree shadows, by a factor of 20 in the case of grove. [ABSTRACT FROM AUTHOR]

The disease caused by Tomato leaf curl New Delhi virus ( ToLCNDV), which is naturally transmitted by the whitefly Bemisia tabaci, causes important economic losses in cucurbit crops. The availability of simple and efficient inoculation protocols and detection methods is necessary for screening varieties and germplasm collections as well as for breeding populations. We evaluated the infectivity of ToLCNDV inocula prepared using three different buffers for mechanical sap inoculation in a susceptible variety of zucchini. We found that inoculum prepared with buffer III, which contains polyvinylpyrrolidone, is highly efficient for mechanical inoculation, with 100% of plants displaying severe symptoms 21 days post-inoculation. Using this buffer, we mechanically inoculated 19 commercial varieties of cucurbit crops (six of cucumber, six of melon and seven of zucchini), evaluated the evolution of symptoms and diagnosed infection using nine different ToLCNDV detection methods (four based on serology, four based on molecular hybridization and one based on PCR detection). The results revealed that all varieties are susceptible, although cucumber varieties display less severe symptoms than those of melon or zucchini. All detection methods were highly efficient (more than 85% of plants testing positive) in melon and zucchini, but in cucumber, the percentage of positive plants detected with serology and molecular hybridization methods ranged from 20.4% with Squash leaf curl virus ( SLCV) antiserum, to 78.5% with DNA extract hybridization. Overall, the best detection results were obtained with PCR, with 92.6%, 92.4% and 98.4% cucumber, melon and zucchini plants, respectively, testing positive. When considering the overall results in the three crops, the best serology and molecular hybridization methods were those using Watermelon chlorotic stunt virus ( WmCSV) antiserum and DNA extract, respectively. The inoculation methodology developed and the information on detection methods are of great relevance for the selection and breeding of varieties of cucurbit crops that are tolerant or resistant to ToLCNDV. [ABSTRACT FROM AUTHOR]

Background: Solanum incanum is a close wild relative of S. melongena with high contents of bioactive phenolics and drought tolerance. S. aethiopicum is a cultivated African eggplant cross-compatible with S. melongena. Despite their great interest in S. melongena breeding programs, the genomic resources for these species are scarce. Results: RNA-Seq was performed with NGS from pooled RNA of young leaf, floral bud and young fruit tissues, generating more than one hundred millions raw reads per species. The transcriptomes were assembled in 83,905 unigenes for S. incanum and in 87,084 unigenes for S. aethiopicum with an average length of 696 and 722 bp, respectively. The unigenes were structurally and functionally annotated based on comparison with public databases by using bioinformatic tools. The single nucleotide variant calling analysis (SNPs and INDELs) was performed by mapping our S. incanum and S. aethiopicum reads, as well as reads from S. melongena and S. torvum available on NCBI database (National Center for Biotechnology Information), against the eggplant genome. Both intraspecific and interspecific polymorphisms were identified and subsets of molecular markers were created for all species combinations. 36 SNVs were selected for validation in the S. incanum and S. aethiopicum accessions and 96% were correctly amplified confirming the polymorphisms. In addition, 976 and 1,278 SSRs were identified in S. incanum and S. aethiopicum transcriptomes respectively, and a set of them were validated. Conclusions: This work provides a broad insight into gene sequences and allelic variation in S. incanum and S. aethiopicum. This work is a first step toward better understanding of target genes involved in metabolic pathways relevant for eggplant breeding. The molecular markers detected in this study could be used across all the eggplant genepool, which is of interest for breeding programs as well as to perform marker-trait association and QTL analysis studies. [ABSTRACT FROM AUTHOR]

The tree tomato ( Solanum betaceum Cav.) is a small tree native to the Andean region cultivated for its juicy fruits, which are having an increasing demand. Tree tomato is morphologically and phenologically different from other Solanum crops and tools for the phenological description of the developmental stages are needed for the enhancement of this emerging crop. We developed a basic and an extended numerical BBCH (Biologische Bundesanstalt, Bundessortenamnt, Chemische Industrie) scales which allow the precise identification of the phenological stages of tree tomato. Eight principal stages are described for germination, leaf development, formation of side shoots, stem elongation, inflorescence emergence, flowering, development of fruit, and ripening of fruit and seed. The basic (two-digit) scale is sufficiently precise for germination, stem elongation, and ripening of fruit and seed. However, for leaf development, formation of side shoots, inflorescence emergence, flowering, and development of fruit the extended (three-digit) scale is considered necessary for an adequate description. The description of the phenological stages is combined with illustrations for clarification. The tree tomato BBCH scale has been validated by characterizing 24 accessions of different varietal groups for traits of agronomic interest and evaluating the differences observed among accessions at specific BBCH developmental stages. The basic and extended BBCH scales represent a useful tool for the description and identification of phenological scales of tree tomato. These scales will be useful for the enhancement of this emerging fruit crop. [ABSTRACT FROM AUTHOR]

Solanum torvum is a highly vigorous relative of eggplant that is resistant to a number of harmful soil-borne diseases and is compatible for grafting with eggplant. Being a potential rootstock, this plant frequently presents poor and erratic germination, which makes its practical use difficult. We used an L8 (2 7 ) orthogonal array design to evaluate the primary effects of seven factors (soaking of seeds, scarification with sodium hypochlorite (NaClO), application of gibberellic acid (GA 3 ), use of potassium mitrate (KNO 3 ) as a moistening agent, cold stratification, application of a heat shock, and light irradiation during germination) at two levels (L0 and L1) using four germination parameters (early and final germination, germination rate and vigour index) in fresh S. torvum seeds. S. torvum seeds had a strong dormancy with no germination in the untreated seeds and high early and final germination (approximately 100%) in certain treatments. An evaluation of the main effects revealed highly positive effects on germination from seed soaking, and the use of GA 3 , KNO 3 , and light irradiation, whereas NaClO scarification had a negative effect. The application of cold stratification and heat shock treatments also had a positive effect on seed germination but to a lesser extent than the other treatments. An improved proposed protocol that consisted of subjecting seeds to soaking, the application of GA 3 and KNO 3 , cold stratification, heat shock, and light irradiation was validated and demonstrated to be highly effective, with seed germination success greater than 60% being observed at 3 days and final germination reaching a plateau at 6 days. A second validation experiment using a commercial growing substrate also showed a high emergence (approximately 50%) at 7 days and a final germination of approximately 80% was recorded with application of the improved protocol. The seed germination protocol that we have developed will facilitate the use of S. torvum as a rootstock for eggplant and its use in breeding programmes. Our results also reveal that orthogonal array designs are a powerful tool for establishing improved protocols for seed germination. [ABSTRACT FROM AUTHOR]

The pepino ( Solanum muricatum ) is a solanaceous vegetatively propagated fruit crop of Andean origin. We provide a detailed description of phenological stages because it is of interest for pepino crop management and research. Given the increasing prominence of this crop, and the fact that it morphologically and developmentally variable, and different from other major solanaceous crops, we have developed a pepino specific BBCH (Biologische Bundesanstalt, Bundessortenamt, CHemische Industrie) numerical scale. Nine principal stages are described for germination/rooting, leaf development, formation of side shoots, main shoot elongation, inflorescence emergence, flowering, development of fruit, ripening of fruit and seed, and senescence. Secondary stages (two-digit scale) have been identified for all principal stages. Complementary descriptions using mesostages (three-digit scale) have been developed for leaf development, formation of side shoots, inflorescence emergence, and flowering phenological stages. A description of all phenological stages combined with illustrations is provided. The utility of the BBCH scale has been validated by comparing several traits of agronomic interest at specific developmental stages in a collection of pepino local varieties, modern cultivars and wild relatives. The BBCH scale developed provides uniform criteria for the description, identification and selection of phenological stages of the pepino and will facilitate the management, breeding and conservation of genetic resources of this crop. [ABSTRACT FROM AUTHOR]