Risk Of Genetic Erosion Research Articles

Genetic diversity and population structure of Polygonatum cyrtonema Hua in China using SSR markers.

Polygonatum cyrtonema Hua is a perennial herbaceous plant of the Polygonatum genus, belonging to the Liliaceae family, with significant medicinal and nutritional value. In China, this species is a traditional medicinal and edible herb with a long history of application and is widely appreciated by the people. However, as the demand for medicinal herbs continues to grow, excessive harvesting has led to the depletion of wild resources and the risk of genetic erosion. In addition, the chaotic cultivation of varieties and the lack of high quality germplasm resources have led to inconsistent quality of medical materials. Therefore, it is urgent to conduct genetic diversity evaluation of this species and establish a sound conservation plan. This study assessed the genetic diversity and population structure of 96 samples collected from seven regions in China using the simple sequence repeat (SSR) molecular marker technology. In this study, a total of 60 alleles (Na) were detected across the 10 polymorphic SSR markers used, with an average of 6.0 alleles generated per locus. The values of polymorphic information content (PIC) values ranged from 0.3396 to 0.8794, with an average value of 0.6430. The average value of the effective number of alleles (Ne) was 2.761, and the average value of the Shannon's information index (I) was 1.196. The population structure analysis indicates that the Polygonatum cyrtonema Hua germplasm can be classified into three subpopulations (JZ, QY, JD) at the molecular level, which corresponds to the previous subgroups identified based on individual plant phenotypic traits. Analysis of Molecular Variance (AMOVA) showed that 74% of the genetic variation was between individuals within populations in different regions. The phylogenetic analysis of the 96 germplasm samples divided them into three main populations. The QY and JD subpopulations are largely clustered together, which could be attributed to their mountainous distribution and the local climate environment. The genetic differentiation coefficient (Fst) value was low at 0.065, indicating relatively low population differentiation. The ratio of the genetic differentiation coefficient (Fst) between the JZ population and the other two populations (QY and JD) is much higher than the ratio between the QY and JD populations. Based on the clustering results and the ratio of the genetic differentiation coefficient (Fst), it can be inferred that the genetic relationship between the QY and JD subpopulations is closer, with a certain degree of genetic differentiation from the JZ subpopulation. This study supports the conservation of germplasm resources of Polygonatum cyrtonema Hua in China and provides new parental material for germplasm genetic improvement and breeding programs.

Variability of morphological descriptors in Sicilian oat (Avena sativa L.) populations

AbstractDue to its rusticity and feasibility of use, oat (Avena sativa L.) represents a crucial agronomic and economic resource for many semiarid environments. Presently, the recourse to new commercial varieties has caused a dramatic lowering of areas covered with the traditional local genotypes, and a severe risk of genetic erosion is emerging. To deepen the knowledge about the autochthonous oat populations, an activity of collection and cataloging across semiarid cropping areas was carried out. Sixteen oat populations were collected from different areas of Sicily and put in a field study for two consecutive years (2014 and 2015) in the experimental farm “Sparacia” (Cammarata, Italy). In both years and all populations, 21 morphological characters, related to different aspects of the whole plant or plant parts, were measured as described in the guidelines Community Plant Variety Office—Office Communautaire des Varietes Vegetales (CPVO‐OCVV) (rif. CPVO‐TP/020/2). Multivariate analysis (MA) was applied to assess the similarity/dissimilarity level among populations, also evaluating the relative discriminatory importance of each selected plant character. Although a strong variability between years did not allow perfect discrimination among genotypes, an association between oat groups emerged based on their prevalent utilization form. Among categorical characters, measurements on glumes and grain provided the best characterization of the populations in both years.

Monitoring Genetic Erosion of Aromatic and Medicinal Plant Species in Alentejo (South Portugal).

The main goal of this work was to study the genetic erosion risk of plants with aromatic, medicinal and gastronomic applications in Portugal, particularly in the Alentejo region. The target species were coriander (Coriandrum sativum L.), hart's pennyroyal (Mentha cervina L.) and pennyroyal (Mentha pulegium L.). The methodology involved direct observations and surveys (2002/2003 and 2011). The GE formula applied in Hammer's studies was used to estimate genetic erosion. The main factors causing genetic erosion were the primary drivers of biodiversity loss: habitat loss, invasive species, and overexploitation influenced by human intervention such as the clearing of watercourses, vegetation control, grazing and desertification. The results indicate a reduction in individuals per species in Alentejo, with a net erosion loss of 11% for M. pulegium, 32% for M. cervina and 33% for C. sativum. The overall loss of accessions (genetic erosion risk) was higher in cultivated accessions (33%) than in wild accessions (11%), with an annual genetic erosion rate of 3.7% and 1.2%, respectively. The annual risk of genetic erosion for M. pulegium accessions collected in a natural habitat was 0.6%, which is much lower than the 3.7% for M. cervina. These results consolidate the importance of collecting and conserving genetic resources.

Genetic diversity analysis and variety identification using SSR and SNP markers in melon

Melon is an important horticultural crop with a pleasant aromatic flavor and abundance of health-promoting substances. Numerous melon varieties have been cultivated worldwide in recent years, but the high number of varieties and the high similarity between them poses a major challenge for variety evaluation, discrimination, as well as innovation in breeding. Recently, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs), two robust molecular markers, have been utilized as a rapid and reliable method for variety identification. To elucidate the genetic structure and diversity of melon varieties, we screened out 136 perfect SSRs and 164 perfect SNPs from the resequencing data of 149 accessions, including the most representative lines worldwide. This study established the DNA fingerprint of 259 widely-cultivated melon varieties in China using Target-seq technology. All melon varieties were classified into five subgruops, including ssp. agrestis, ssp. melo, muskmelon and two subgroups of foreign individuals. Compared with ssp. melo, the ssp. agrestis varieties might be exposed to a high risk of genetic erosion due to their extremely narrow genetic background. Increasing the gene exchange between ssp. melo and ssp. agrestis is therefore necessary in the breeding procedure. In addition, analysis of the DNA fingerprints of the 259 melon varieties showed a good linear correlation (R2 = 0.9722) between the SSR genotyping and SNP genotyping methods in variety identification. The pedigree analysis based on the DNA fingerprint of ‘Jingyu’ and ‘Jingmi’ series melon varieties was consistent with their breeding history. Based on the SNP index analysis, ssp. agrestis had low gene exchange with ssp. melo in chromosome 4, 7, 10, 11and 12, two specific SNP loci were verified to distinguish ssp. agrestis and ssp. melon varieties. Finally, 23 SSRs and 40 SNPs were selected as the core sets of markers for application in variety identification, which could be efficiently applied to variety authentication, variety monitoring, as well as the protection of intellectual property rights in melon.

In Vitro Propagation by Axillary Shoot Culture and Somatic Embryogenesis of Daucus carota L. subsp. sativus, ‘Polignano’ Landrace, for Biodiversity Conservation Purposes

Carrots are a multi-purpose vegetable; hence, they have become a very popular consumers’ choice, also thanks to their nutritional value with health benefits. Several varieties and landraces exist of carrot (Daucus carota L. ssp. sativus). In Apulia (Italy), for example, a multicolored carrot landrace is present, the Polignano carrot (PC), threatened by the risk of genetic erosion. With the purpose of verifying the possibility of using in vitro culture for ex situ conservation purposes of PC, a rapid and reliable protocol for micropropagation and a highly efficient somatic embryogenesis protocol have been set up. For micropropagation studies, axillary buds from taproot were used as initial explants. Supplementation on basal medium (BM, a Murashige–Skoog modified medium) with low cytokinine (6-benzyladenine, BA, 0.22 μM) dosage was enough to obtain a good multiplication rate, also depending by the PC color. Rooting of proliferated shoots occurred easily in hormone-free medium and acclimatization was successfully reached in 6 weeks. Somatic embryos were formed from embryogenic callus induced by taproot sections placed on 2,4-dichlorophenoxyacetic acid (2,4-D)-added medium. After in vitro conversion in hormone-free medium, somatic embryos were also successfully acclimatized. Both microplants and somatic embryos produced true-to-type taproots (multicolored carrots), demonstrating the suitability of in vitro techniques for biodiversity conservation purposes.

Genetic diversity and population structure of cowpea [Vigna unguiculata (L.) Walp.] accessions from Togo using SSR markers.

Cowpea [Vigna unguiculata (L.) Walp.] is a crop with significant agronomic and nutritional value. In Togo, the crop is very appreciated by local people. It is the third food habit in Togo after maize and rice. However, several accessions of cowpea cultivated in Togo are now prone to extinction, creating a risk of genetic erosion. It is therefore urgent to assess the genetic diversity of accessions in order to set up a good conservation program. To achieve this, genetic diversity and phylogenetic relationships among 70 accessions of cowpea collected in the five (5) administrative regions of Togo were assessed using Simple Sequence Repeat (SSR) molecular markers. The twenty-eight SSR primers used in this study generated a total of 164 alleles with an average of 5.82 alleles per locus. Polymorphic Information Content (PIC) values ranged from 0.20 to 0.89 with an average value of 0.58. Population structure analysis using model-based revealed that the cowpea germplasm was grouped into two subpopulations. The analysis of molecular variance (AMOVA) revealed that 98% of genetic variation existed among accessions within regions. The fixation index (Fst) value, which was 0.069 was low, indicating relatively low population differentiation. The phylogenetic analysis grouped the 70 accessions into two main groups that can be further divided into four groups independent of their origins. This study provides a foundation for a Togolese cowpea germplasm conservation program and can serve for the selection of parental material for further studies aimed at the genetic improvement of local germplasm.

Chloroplast DNA Diversity of Tunisian Barley Landraces as Revealed by cpSSRs Molecular Markers and Implication for Conservation Strategies.

In Tunisia, barley local landraces are still cropped for human and animal consumption in some subsistence farming systems under marginal and stressed conditions. These high-value genetic resources present a potential source of resistance genes to biotic and abiotic stresses useful for both national and international breeders. Actually, they are represented by threatened small populations, which face a high risk of genetic erosion and progressive substitution by modern varieties. In this study, the genetic diversity of 60 Tunisian barley landraces was assessed using six chloroplast microsatellites. All loci were found polymorphic, with 2 or 3 alleles per locus. Thirteen alleles were detected across the studied sample, which were combined into 8 haplotypes, giving a haplotype diversity (Hd) of 0.847. High punctual and haplotype genetic diversity was observed for Tunisian barley landraces when compared to other germplasms from other regions of the world. The genetic structure analysis revealed two major clusters of Tunisian barley landraces, which confirms their multiorigin. This result was corroborated by the median-joining network showing the genetic relationships among the eight detected haplotypes. The AMOVA analysis revealed that 83% of the genetic variation is between populations, which requires the in situ and ex situ conservation of plant material for all Tunisian populations of barley landraces. Information on genetic variation within the chloroplast genome is of great interest to ensure an efficient conservation strategy that takes into account the preservation of the various maternal lineages of Tunisian barley.

On the feasibility of estimating contemporary effective population size (Ne) for genetic conservation and monitoring of forest trees

Estimates of contemporary effective population size (Ne) can provide valuable information for genetic conservation and monitoring, pinpointing populations at higher risk of genetic erosion, decreased fitness, maladaptation and, ultimately, demographic decline. There are however potential limitations in the application of commonly employed genetic estimators of contemporary Ne to widespread forest tree populations. Genetic isolation by distance within populations, small and spatially restricted samples, among-population gene flow and overlapping generations are factors that can potentially affect the accuracy of marker-based estimates of contemporary Ne, depending on the demographic scenario. In particular, we illustrate the uncertainty faced by forest researchers and managers when interpreting contemporary Ne estimates obtained for continuously distributed tree populations with large census size N. To that end, we use previously published genotypic data of 21 Pinus pinaster populations, including distinct sampling schemes, together with a widely used method based on linkage disequilibrium patterns observed in a single (one-time) population sample. We hypothesize that spatially restricted sampling might be the main putative factor behind the apparently low Ne/N estimates obtained for the large and continuously-distributed populations studied here. Because of its statistically-inherent assessment difficulty, we call for caution when interpreting marker-based estimates of contemporary Ne for monitoring widely-distributed tree populations or small genetic conservation units embedded within large continuous tree populations.

Screening South American Potato Landraces and Potato Wild Relatives for Novel Sources of Late Blight Resistance.

Late blight (LB) caused by the oomycete Phytophthora infestans is one of the most important biotic constraints for potato production worldwide. This study assessed 508 accessions (79 wild potato species and 429 landraces from a cultivated core collection) held at the International Potato Center genebank for resistance to LB. One P. infestans isolate belonging to the EC-1 lineage, which is currently the predominant type of P. infestans in Peru, Ecuador, and Colombia, was used in whole plant assays under greenhouse conditions. Novel sources of resistance to LB were found in accessions of Solanum albornozii, S. andreanum, S. lesteri, S. longiconicum, S. morelliforme, S. stenophyllidium, S. mochiquense, S. cajamarquense, and S. huancabambense. All of these species are endemic to South America and thus could provide novel sources of resistance for potato breeding programs. We found that the level of resistance to LB in wild species and potato landraces cannot be predicted from altitude and bioclimatic variables of the locations where the accessions were collected. The high percentage (73%) of potato landraces susceptible to LB in our study suggests the importance of implementing disease control measures, including planting susceptible genotypes in less humid areas and seasons or switching to genotypes identified as resistant. In addition, this study points out a high risk of genetic erosion in potato biodiversity at high altitudes of the Andes due to susceptibility to LB in the native landraces, which has been exacerbated by climatic change that favors the development of LB in those regions.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Genetic erosion detected in a specialist mammal living in a fast‐developing environment

AbstractFragmentation of habitat is a major threat across a wide range of taxa. Subsequent effects include reduced population sizes and isolation of populations. Both can have detrimental consequences for populations as they increase the risk of genetic erosion. While it is critical to prevent and, if required, reverse genetic erosion, we often lack adequate data to assess whether and how much genetic erosion has occurred. Here, we present a genetic monitoring study where we investigated changes in genetic diversity and genetic patterns in a threatened, specialist mammal, the koala (Phascolarctos cinereus). Our study population inhabits an increasingly fragmented landscape and has experienced a sharp decline in population size within the past three decades. We used 1038 single nucleotide polymorphic loci (SNPs) to compare measures of genetic diversity between samples collected in 2018 and in 2006 (two generations prior) and investigated simultaneous changes in the environment. We found a decline in both heterozygosity and effective population size (Ne), and an increase in sub‐structuring, average relatedness, and inbreeding (FIS) alongside an increasingly threatening and more fragmented environment. Given the extent of genetic erosion in only two generations, we urge consideration for the implementation of mitigation measures for this population and for threatened populations in similar conditions. Our study further emphasizes the importance of effective management of at‐risk populations including monitoring of genetic erosion.

Morphological Characterization of Two Light Italian Turkey Breeds.

Simple SummaryGenetic resources on turkeys are scarce, considering both domestic and wild birds. Smaller, dark-colored Italian heritage breeds such as Brianzolo and Nero d’Italia have been selected for centuries in outskirt areas due to their coping ability in poor environments and high brooding ability. However, they are in danger of extinction. EC Council Regulations on organic farming strongly recommend using local genetic resources and conserving biodiversity. Phenotypical characterization is a basic step in biodiversity conservation; therefore, in this article, we present morphometric and colorimetric analysis results of 46 birds belonging to each of the considered breeds. We considered 18 parameters: morphometries, morphological indexes, linear evaluation, and colorimetric indexes as characterizing factors in breeds differentiation. Differences in weight with clear sexual dimorphism were recorded. Massiveness indexes were in favor of the slightly more compact Brianzolo breed. The extremely fair skin and dark shank of the Nero d’Italia turkey were revealed by colorimetric analysis. The effectiveness of morphological analysis in breeds differentiation, useful data in heritage breeds conservation, and characterization were considered control parameters in classifying animal products.We aimed to investigate the variability within turkeys’ phenotypical traits in two Italian heritage breeds: Brianzolo (BRZ) and Nero d’Italia (NIT), as analyzed through morphometry, morphometrical indexes, linear scoring, and colorimetric indexes. A total of 92 birds were measured, weighed, and scored (46 NIT: M/F = 19/27; 46 BRZ: M/F = 19/27). Live weight (LW), total body length (BL, excluding feathers), keel length (KL), chest circumference (BC), wingspan (WS), shank length (SL), shank diameter (SD), and shank circumference (SC). Massiveness (MASS), stockiness (STOCK), and long-leggedness (LLEG) indexes were also calculated. The body condition score (BCS) applied a linear evaluation to nutritional status and muscular development. Colorimetric indexes (L*, a*, b*) were recorded, sampling skin and shank. Data were analyzed using GLM procedures and PCA. NIT was the heaviest breed (4.89 vs. 4.07 kg; p ≤ 0.05). In both breeds, sexual dimorphism was visible in the LW trait with males (M) weighing significantly heavier than females (F) (p ≤ 0.05). NIT birds recorded the highest BL values: 58.44 vs. 57.15 cm (p ≤ 0.05). MASS was higher in NIT (8.26 vs. 7.0; p ≤ 0.05), and STOCK was higher in BRZ (82.62 vs. 85.37; p ≤ 0.05). Colorimetric indexes revealed significant differences in skin lightness (L*) and redness (a*). For shank color, the breed significantly affected differences in the indexes. This study characterizes these breeds at high risk of genetic erosion and extinction, which will help the morphological standardization of birds and the enhancement of genetic variability

Crop Wild Relatives (CWRs) Threatened and Endemic to Italy: Urgent Actions for Protection and Use.

Simple SummaryCrop wild relatives (CWRs) are wild plants with an indirect use derived from their relatively close genetic relationship to a crop and have contributed to crop domestication for millennia. Nowadays, due to human overexploitation of plants and other environmental resources, they are threatened and hence need protection to guarantee plant evolution and food supply for the future of human generations. This concept is especially true for endemic CWRs, which have a greater risk of genetic erosion and/or extinction and need more urgent, specific targeted actions. In this study, the Italian threatened and endemic CWRs, often exclusive of one administrative region, are discussed based on the Annex I Priority crops of the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA, FAO).An updated overview of the 29 threatened crop wild relatives (CWRs) endemic to Italy is presented, namely: Arrhenatherum elatius subsp. nebrodense, Barbarea rupicola, Brassica baldensis, Brassica glabrescens, Brassica macrocarpa, Brassica rupestris subsp. hispida, Brassica rupestris subsp. rupestris, Brassica tardarae, Brassica trichocarpa, Brassica tyrrhena, Brassica villosa subsp. bivonana, Brassica villosa subsp. brevisiliqua, Brassica villosa subsp. drepanensis, Brassica villosa subsp. tineoi, Brassica villosa subsp. villosa, Daucus broteroi, Daucus carota subsp. rupestris, Daucus nebrodensis, Diplotaxis scaposa, Festuca centroapenninica, Lathyrus apenninus, Lathyrus odoratus, Malus crescimannoi, Phalaris arundinacea subsp. rotgesii, Vicia brulloi, Vicia consentina, Vicia giacominiana, Vicia ochroleuca subsp. ochroleuca, Vicia tenuifolia subsp. elegans. Data concerning geographical distribution, ecology (including plant communities and habitats of the Directive 92/43/EEC), genetics (chromosome number, breeding system, and/or the existence of gene pools), threat status at the national and international level (Red Lists), key plant properties, and in situ and ex situ conservation were analyzed and shown. At present, most of the listed endemic CWRs, 23 out of 29, have no gene pool at all, so they are CWRs only according to the taxon group and not according to the gene pool concept. In addition, there is a serious lack of data on the ex situ conservation in gene banks, with 16 species identified as high priority (HP) while 22 taxa have high priority (A) for in situ conservation. With the aim of their protection, conservation, and valorization, specific and urgent actions are recommended.

Ethnobotanical study of pumpkin (Cucurbita moschata Duchesne) landraces in Benin

BackgroundPumpkin, Cucurbita moschata Duchesne, is important food resource due to their nutritional composition. Despite their food advantages, they still remain underutilized crops in Africa and particularly in Benin. No documented information is available on the knowledge of producers on the use, conservation and commercialization of Cucurbita moschata. The objectives of this study are to (i) collect various accessions of pumpkin on the basis of local taxonomic criteria in Benin; (ii) collect information on uses of pumpkin in Benin. To this end, an investigation was carried out in the departments of Couffo (Dogbo, Djakotomey, Klouékanme and Aplahoué) and Borgou (Parakou and N’dali).MethodsOne hundred twenty (120) farmers grouped into 06 different ethnic groups (Adja, Bariba, Bialy, Fon, Gourmantché and Zarma) were interviewed. Six pumpkin landraces were identified in 19 villages surveyed through systematic census of farmers supported by the snowball technique.ResultsVarietal diversity on a municipal level varied from two to four. Pumpkin was mainly cultivated by men and about 15% were cultivated in cultural association with maize, cassava, cowpea and groundnut. The harvested fruits were used for consumption, commercial, therapeutic and occult purposes. However, about 48% of producers have abandoned its production mainly due to production and marketing constraints. This abandonment could induce a risk of genetic erosion of this species. Thus, the conservation and an enhancement of the genetic resources of this species is essential.ConclusionsThis study made it possible to establish farmers’ knowledge on the utilization and production of pumpkin landraces, and identify the varietal diversity of Benin landraces of pumpkin.

Custodians of common bean diversity in Rio de Janeiro state, Brazil: revealing their socioeconomic and environmental profile

ABSTRACT This study revealed the profile of common bean farmers in the state of Rio de Janeiro, Brazil. One hundred and thirty-eight farmers from 24 municipalities were interviewed. We observed that common beans are a key component of agricultural systems in this state, with the number of varieties managed by family varying widely (from one to 11). This variation was influenced by socioeconomic, ecogeographic, and cultural factors. An impressive number of common bean varieties were being managed by farmers who resided at mid-altitude zones and combine subsistence crops with market-oriented cultivation. In three of five mesoregions visited, the traditional agriculture has been affected by climate changes. The majority of farmers who managed low diversity of common beans, and all farmers who stopped growing this crop in recent years resided in these regions. Facing the risk of genetic erosion, farmers, researchers and extension workers involved in this research are building strategies to strengthen the conservation of this local germplasm. Actions are underway with public agencies to enhance the importance of self-consumption cultures for food security, local development and conservation of cultural traditions. Among these, we highlight the publication of Catálogo da Diversidade Feijão-comum do estado do Rio de Janeiro. In addition, an ex-situ conservation agreement was established for the varieties, with a strong participation of custodians, to provide greater security to the local common bean germplasm.

New insights into the intraspecific cytoplasmic DNA diversity, maternal lineages classification and conservation issues of Tunisian pearl millet landraces.

Tunisian pearl millet (Pennisetum glaucum L.) landraces are still growing in contrasting agro-ecological environments and are considered potentially useful for national and international breeders. Despite its genetic potential, the cropping areas of this species are still limited and scattered which increases the risk of genetic erosion. The chloroplast DNA polymorphism and maternal lineages classification of forty nine pearl millet landraces representing seven populations covering the main distribution area of this crop in Tunisia were undertaken based on informative cpSSR molecular markers. A total of 21 alleles combining to 9 haplotypes were detected with a mean value of 3.5 alleles per locus and a haplotype genetic diversity (Hd) of 0.82. The number of chloroplast haplotypes per population ranged from 1 to 4 with an average of 1.28. The haplotypes median-joining network and UPGMA analyses revealed two probable ancestral maternal lineages with a differential pearl millet seed-exchange rate between the investigated areas. Northern and Central populations presented unique genetic backgrounds while historical farmers' practices in the South-East area resulted in the isolation of their own local landraces. The genetic evidences strongly support at least two introduction origins of pearl millet in Tunisia, one in the North and the other in the South followed by distinct local dispersal histories. Complementary in-situ and ex-situ conservation strategies taking into account the conservation of the maternal lineage cytoplasmic diversity are required. The investigated chloroplast SSRs provide useful molecular markers which could be used in further genetic studies and breeding surveys of pearl millet genetic resources.

First morphological characterization of autochthonous olive (Olea europaea L.) denominations from central and eastern of Algeria

Olive (Olea europaea L.) resources in Algeria are very little investigated. In fact, a total of 60 denominations have been the subject of characterization studies and they are cited in the bibliography but only 36 varieties are described and listed in the catalog of Algerian varieties of olive tree. In this work, a study on the diversity by mean of a field survey followed by morphological characterization, an estimate of the Shannon diversity index of a set of denominations collected in central and eastern of Algeria were carried out. The survey allowed us to note the existence of 33 denominations never mentioned in the bibliography. Morphological characterization based on the characteristics of tree, fruit and endocarp allowed us to a morphological description of 23 denominations. The Principal Component Analysis, Multiple Correspondence Analysis and Ascending Hierarchical Classification analysis allowed us to classify them into a few groups. The value of the relative diversity of all denominations is slightly below the average (0.42). The results obtained in this work provide very useful information on certain morphological characteristics of the studied denominations and indicate the critical conditions in which several denominations are found, which constitutes a great risk of genetic erosion.

Cochlospermum planchonii Hook.f. ex Planch. and Cochlospermum tinctorium Perrier ex A. Rich.: extent of knowledge and prospects for sustainable use in West Africa

Cochlospermum planchonii Hook.f. ex Planch. and Cochlospermum tinctorium Perrier ex A. Rich. are two wild edible plant species (WEPs), widely used in the West African Sudanian zone. Their parts are used as food additive, fodder, medical-magic and ethnoveterinary purposes, dye and arts. Unfortunately, the overexploitation of their rootstocks constitutes a great threat. While, an increasing number of studies reported on their uses, socio-economic importance, biological properties, and the anthropogenic pressure, knowledge on their reproductive biology, threats, domestication, and conservation status are still lacking. It therefore becomes crucial to systematically review literature on the current knowledge to identify research gaps and future research. Hence, this review aimed to critically synthetize knowledge, and gaps therein, to highlight future research for sustainable use and conservation of both species. To this end, publications were searched online in Web of Science, PubMed, Google Scholar, Science Direct, Springer Online and Research Gate, using following keywords: “taxonomy”, “distribution”, “ecology”, “botanical description”, “structural characteristics”, “vernacular names”, “uses”, “plant parts used”, “phytochemical” and “pharmacological properties”, “economy”, “propagation”, “pollination”, “reproduction”, “threats”, “conservation” and “domestication” in combination with “C. planchonii” or “C. tinctorium”, “False-cotton”. Out of 423 publications initially recorded, 165 were retained, of which 153 conducted in West Africa; the remaining 12 tackled botanical and taxonomical issues. Most of the publications addressed ethnobotany, chemical and pharmacological properties. Information obtained was compiled, critically analyzed, and discussed; knowledge gaps were keyed out and potential future research was highlited. The review confirmed the over-exploitation of both species mainly for human livelihoods. Both species were valuable sources of compounds and showed various pharmacological activities. A risk of genetic erosion was reported due overharvesting of their rootstocks whose powder was highly marketable. Future studies on their reproductive biology could enable their cultivation in order to reduce anthropogenic pressure and promote their sustainable use and conservation.

Study on physical characteristics of Ceratonia siliqua pods using specific biochemical markers

Two samples of carob (Ceratonia siliqua) pods were assessed for the morphological and physiological characteristics in the Mediterranean region. Ceratonia siliqua is considered as a versatile plant with edible pods and as a raw material in pharmaceuticals and cosmetic industries, thus, accentuating its commercial value. The risk of genetic erosion has rendered an urgency to study and describe the actual consistency of carob pods. Therefore, this experiment was conducted on carob collected from two regions, Aleppo in Syria and Crete in Greece. Pods from every sample were analyzed for physical characteristics like length, width, thickness, number of seeds per pod, seed weight and pulp weight. Specific biochemical markers were determined for the methanol extract of carob pods from the two samples of seeds. In the findings we noticed a clear difference between the two samples in most physical traits except number of seeds per pod. There was no significant difference in the specific biochemical markers between the two samples of carob cultivars. The knowledge of morphological and physiological characters is of great importance for the industries and conservation purposes, thus in-depth studies in this area are imperative.

A new SNP genotyping technology Target SNP-seq and its application in genetic analysis of cucumber varieties

To facilitate the utility of SNP-based genotyping, we developed a new method called target SNP-seq which combines the advantages of multiplex PCR amplification and high throughput sequencing. Compared with KASP, Microarrays, GBS and other SNP genotyping methods, target SNP-seq is flexible both in SNPs and samples, yields high accuracy, especially when genotyping genome wide perfect SNPs with high polymorphism and conserved flanking sequences, and is cost-effective, requiring 3 days and $7 for per DNA sample to genotype hundreds of SNP loci. The present study established a DNA fingerprint of 261 cucumber varieties by target SNP-seq with 163 perfect SNPs from 4,612,350 SNPs based on 182 cucumber resequencing datasets. Four distinct subpopulations were found in 261 Chinese cucumber varieties: the north China type, the south China type, the Europe type, and the Xishuangbanna type. The north China type and Xishuangbanna type harbored lower genetic diversity, indicating greater risk of genetic erosion in these two subpopulations. Furthermore, a core set of 24 SNPs was able to distinguish 99% of the 261 cucumber varieties. 29 core cucumber backbone varieties in China were identified. Therefore, target SNP-seq provides a new way to screen out core SNP loci from the whole genome for DNA fingerprinting of crop varieties. The high efficiency and low cost of target SNP-seq is more competitive than the current SNP genotyping methods, and it has excellent application prospects in genetic research, as well as in promoting plant breeding processes in the near future.

Recovery, Assessment, and Molecular Characterization of Minor Olive Genotypes in Tunisia.

Olive is one of the oldest cultivated species in the Mediterranean Basin, including Tunisia, where it has a wide diversity, with more than 200 cultivars, of both wild and feral forms. Many minor cultivars are still present in marginal areas of Tunisia, where they are maintained by farmers in small local groves, but they are poorly characterized and evaluated. In order to recover this neglected germplasm, surveys were conducted in different areas, and 31 genotypes were collected, molecularly characterized with 12 nuclear microsatellite (simple sequence repeat (SSR)) markers, and compared with 26 reference cultivars present in the Tunisian National Olive collection. The analysis revealed an overall high genetic diversity of this olive’s germplasm, but also discovered the presence of synonymies and homonymies among the commercialized varieties. The structure analysis showed the presence of different gene pools in the analyzed germplasm. In particular, the marginal germplasm from Ras Jbal and Azmour is characterized by gene pools not present in commercial (Nurseries) varieties, pointing out the very narrow genetic base of the commercialized olive material in Tunisia, and the need to broaden it to avoid the risk of genetic erosion of this species in this country.