scholarly journals Genetic diversity and population structure of the sweet leaf herb, Stevia rebaudiana B., cultivated and landraces germplasm assessed by EST-SSRs genotyping and steviol glycosides phenotyping

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Patrick Cosson ◽  
Cécile Hastoy ◽  
Luis Ernesto Errazzu ◽  
Carlos Jorge Budeguer ◽  
Philippe Boutié ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Polymorphic Information Content ◽  
Germplasm Collection ◽  
Stevia Rebaudiana ◽  
Sweet Taste ◽  
Genome Project ◽  
Steviol Glycosides ◽  
Genomic Tools ◽  
Wide Range ◽  
Genetic Clusters

Abstract Background Stevia rebaudiana (Asteraceae), native from Paraguay, accumulates steviol glycosides (SGs) into its leaves. These compounds exhibit acaloric intense sweet taste which answers to consumer demands for reducing daily sugar intake. Despite the developpement of S. rebaudiana cultivation all over the world, the development of new cultivars is very recent, in particular due to a colossal lack of (1) germplasm collection and breeding, (2) studies on genetic diversity and its structuring, (3) genomic tools. Results In this study, we developped 18 EST-SSR from 150,258 EST from The Compositae Genome Project of UC Davis (http://compgenomics.ucdavis.edu/data/). We genotyped 145 S. rebaudiana individuals, issued from thirty-one cultivars and thirty-one landraces of various origins worldwide. Markers polymorphic information content (PIC) ranged between 0.60 and 0.84. An average of 12 alleles per locus and a high observed heterozygoty of 0.69 could be observed. The landraces revealed twice as many private alleles as cultivars. The genotypes could be clustered into 3 genetic populations. The landraces were grouped in the same cluster in which the oldest cultivars “Eirete” and “MoritaIII” type are also found. The other two clusters only include cultivated genotypes. One of them revealed an original genetic variability. SG phenotypes could not discriminate the three genetic clusters but phenotyping showed a wide range of composition in terms of bitter to sweet SGs. Conclusion This is the first study of genetic diversity in Stevia rebaudiana involving 145 genotypes, including known cultivars as well as landrace populations of different origin. This study pointed out the structuration of S. rebaudiana germplasm and the resource of the landrace populations for genetic improvement, even on the trait of SG’s composition.

scholarly journals Performance and Genetic Diversity among a Collection of Stevia Rebaudiana Bertoni Accessions Using Microsatellite Markers in Malaysia

Proceedings ◽  
2020 ◽  
Vol 36 (1) ◽  
pp. 221
Author(s):  
Pedram Kashiani ◽  
Ghizan Saleh ◽  
Ridzwan Che Rus
Keyword(s):  
Genetic Diversity ◽  
Stevia Rebaudiana ◽  
Day Length ◽  
Steviol Glycosides ◽  
Agronomic Performance ◽  
Heterotic Groups ◽  
Stevia Rebaudiana Bertoni ◽  
Leaf Weight ◽  
Wide Range ◽  
Improvement Programs

The plant Stevia rebaudiana Bertoni (2n=22) is a native of certain regions of South America particularly in Paraguay. It is a short-term plant and needs three months to complete one cycle of vegetative growth and flowering. With days less than 13 hours in tropical countries, stevia plants flower early, resulting in low yield. In addition, the early bud emergence under the short-day length condition causes the sugar content in stevia leaves to reduce drastically, making them no longer valuable for commercial use. The stevia accessions available in Malaysia today are limited in number and poor in performance, emphasizing the necessity of varietal improvement programs. Assessment of genetic variability, diversity and intrarelationships is an essential step for such breeding programs. This study aims to evaluate agronomic performance of among 21 stevia accessions, namely SRBA-1 to SRBA-21, collected from different origins and to reveal genetic diversity utilizing 52 novel microsatellites. Evaluation of agronomic traits revealed wide range of variation in leaf weight, dry leaf weight, plant height, number of branches, stevioside; rebaudioside A (Reb A), rebaudioside C (Reb C) and total steviol glycosides (TSG). The total genetic diversity detected among the accessions through amplification of the 43 polymorphic microsatellites showed that almost all markers had deviation from Hardy–Weinberg equilibrium (Ho>He). Three distinct heterotic groups were identified among the accessions based on their agronomic performance and molecular characteristics. Crosses among different accessions coming from different heterotic groups can be further used to produce potential stevia variety for plantation in Malaysia.

scholarly journals The role of environment, local adaptation and past climate fluctuation on the amount and distribution of genetic diversity in the teosinte in Mexico

2019 ◽  
Author(s):  
Jaime Gasca-Pineda ◽  
Yocelyn T. Gutiérrez-Guerrero ◽  
Erika Aguirre-Planter ◽  
Luis E. Eguiarte
Keyword(s):  
Genetic Diversity ◽  
Local Adaptation ◽  
Environmental Conditions ◽  
Wide Distribution ◽  
Wide Range ◽  
Significant Genetic Structure ◽  
Nuclear Microsatellite ◽  
Genetic Clusters ◽  
Assignment Analysis ◽  
Climate Fluctuation

AbstractWild maize, commonly known as teosinte, has a wide distribution in central Mexico and inhabits a wide range of environmental conditions. According to previous studies, the environment is a determinant factor for the amount and distribution of genetic diversity. In this study, we used a set of neutral markers to explore the influence of contemporary factors and historical environmental shifts on genetic diversity, including present and three historical periods. Using a set of 22 nuclear microsatellite loci, we genotyped 527 individuals from 29 localities. We found highly variable levels of genetic diversity (Z. m. parviglumis HE= 0.3646–0.7699; Z. m. mexicana HE= 0.5885–0.7671) and significant genetic structure among localities (average DEST= 0.4332). Also, we recovered significant values of heterozygote deficiency (average FIS= 0.1796) and variable levels of selfing (sg2=0.0–0.3090). The Bayesian assignment analysis yielded four genetic clusters dividing the sample into subspecies, that in turn, were separated into two clusters. Environmental conditions played a strong influence in the distribution of genetic diversity, as demographic analysis and changes in species range revealed by modeling analyses were consistent. We conclude that current genetic diversity in teosinte is the result of a mixture of local adaptation and genetic isolation along with historical environmental fluctuations.

scholarly journals Transcriptome wide SSR discovery cross-taxa transferability and development of marker database for studying genetic diversity population structure of Lilium species

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Manosh Kumar Biswas ◽  
Mita Bagchi ◽  
Ujjal Kumar Nath ◽  
Dhiman Biswas ◽  
Sathishkumar Natarajan ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Large Scale ◽  
Polymorphic Information Content ◽  
Pcr Amplification ◽  
Efficient Manner ◽  
Lilium Species ◽  
Population Structure Analysis ◽  
Wide Range ◽  
Functional Molecular Markers

Abstract Lily belongs to family liliaceae, which mainly propagates vegetatively. Therefore, sufficient number of polymorphic, informative, and functional molecular markers are essential for studying a wide range of genetic parameters in Lilium species. We attempted to develop, characterize and design SSR (simple sequence repeat) markers using online genetic resources for analyzing genetic diversity and population structure of Lilium species. We found di-nucleotide repeat motif were more frequent (4684) within 0.14 gb (giga bases) transcriptome than other repeats, of which was two times higher than tetra-repeat motifs. Frequency of di-(AG/CT), tri-(AGG/CTT), tetra-(AAAT), penta-(AGAGG), and hexa-(AGAGGG) repeats was 34.9%, 7.0%, 0.4%, 0.3%, and 0.2%, respectively. A total of 3607 non-redundant SSR primer pairs was designed based on the sequences of CDS, 5′-UTR and 3′-UTR region covering 34%, 14%, 23%, respectively. Among them, a sub set of primers (245 SSR) was validated using polymerase chain reaction (PCR) amplification, of which 167 primers gave expected PCR amplicon and 101 primers showed polymorphism. Each locus contained 2 to 12 alleles on average 0.82 PIC (polymorphic information content) value. A total of 87 lily accessions was subjected to genetic diversity analysis using polymorphic SSRs and found to separate into seven groups with 0.73 to 0.79 heterozygosity. Our data on large scale SSR based genetic diversity and population structure analysis may help to accelerate the breeding programs of lily through utilizing different genomes, understanding genetics and characterizing germplasm with efficient manner.

scholarly journals Genetic Diversity and Population Structure of Cowpea [Vigna unguiculata (L.) Walp.] Germplasm Collected from Togo Based on DArT Markers

Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1451
Author(s):  
Kodjo M. Gbedevi ◽  
Ousmane Boukar ◽  
Haruki Ishikawa ◽  
Ayodeji Abe ◽  
Patrick O. Ongom ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Improvement ◽  
Agricultural Research ◽  
Polymorphic Information Content ◽  
Germplasm Collection ◽  
Mean Value ◽  
Economic Life ◽  
Dart Markers ◽  
Crop Genetic Diversity

Crop genetic diversity is a sine qua non for continuous progress in the development of improved varieties, hence the need for germplasm collection, conservation and characterization. Over the years, cowpea has contributed immensely to the nutrition and economic life of the people in Togo. However, the bulk of varieties grown by farmers are landraces due to the absence of any serious genetic improvement activity on cowpea in the country. In this study, the genetic diversity and population structure of 255 cowpea accessions collected from five administrative regions and the agricultural research institute of Togo were assessed using 4600 informative diversity array technology (DArT) markers. Among the regions, the polymorphic information content (PIC) ranged from 0.19 to 0.27 with a mean value of 0.25. The expected heterozygosity (He) varied from 0.22 to 0.34 with a mean value of 0.31, while the observed heterozygosity (Ho) varied from 0.03 to 0.07 with an average of 0.05. The average inbreeding coefficient (FIS) varied from 0.78 to 0.89 with a mean value of 0.83, suggesting that most of the accessions are inbred. Cluster analysis and population structure identified four groups with each comprising accessions from the six different sources. Weak to moderate differentiation was observed among the populations with a genetic differentiation index varying from 0.014 to 0.117. Variation was highest (78%) among accessions within populations and lowest between populations (7%). These results revealed a moderate level of diversity among the Togo cowpea germplasm. The findings of this study constitute a foundation for genetic improvement of cowpea in Togo.

Elucidation of genetic diversity base in Calotropis procera – a potentially emerging new fibre resource

2020 ◽  
Vol 18 (3) ◽  
pp. 159-167 ◽  
Author(s):  
Aasim Majeed ◽  
Bhawana Goel ◽  
Vandana Mishra ◽  
Ravinder Kohli ◽  
Pankaj Bhardwaj
Keyword(s):  
Genetic Diversity ◽  
De Novo ◽  
Polymorphic Information Content ◽  
Geographic Distance ◽  
Germplasm Collection ◽  
Initial Step ◽  
Breeding Systems ◽  
Calotropis Procera ◽  
Wild Populations ◽  
Breeding Programmes

AbstractCalotropis procera is emerging as a new, yet undomesticated, resource of fibre comparable to cotton and kapok. Screening of efficient genotypes from its wild populations would be a useful pre-domestication process. The desired genotypes can then be improved through conventional breeding programmes to develop a domesticated variety. Molecular markers play a major role in modern breeding systems. Thus, an efficient marker resource for C. procera would prove useful in germplasm selection during breeding programmes. In this study, we undertook an initial step of Simple sequence repeats (SSR) marker development for C. procera, which could be applied for germplasm selection. Furthermore, using the developed markers, we assessed the genetic diversity base within its wild populations which could be useful to identify the hotspot areas of germplasm collection. Out of 94,636 de novo assembled transcripts, 9148 sequences were found to contain 12,884 SSRs at a density of 5.5 SSRs/Mb. Twelve SSRs were found as polymorphic with a mean polymorphic information content of 0.575. We observed a moderate level of genetic diversity (Na = 3.625, Ho = 0.58) in the studied populations. Mantel's test showed significant correlation between the geographic distance and the genetic distance (r = 0.147, P = 0.010). Sirsa was found as a genetically most diverse population followed by Barnala while Gurdaspur was found with the least genetic diversity. These genetically diverse populations can serve as an important resource for effective germplasm collection for breeding programmes.

scholarly journals Application of in vitro stevia (Stevia rebaudiana Bertoni) cultures in obtaining steviol glycoside rich material

2015 ◽  
Vol 61 (1) ◽  
pp. 50-63 ◽  
Author(s):  
Aleksandra Luwańska ◽  
Aleksandra Perz ◽  
Grażyna Mańkowska ◽  
Karolina Wielgus
Keyword(s):  
Food Industry ◽  
Stevia Rebaudiana ◽  
Sweet Taste ◽  
Steviol Glycosides ◽  
Practical Applications ◽  
Culture Techniques ◽  
Steviol Glycoside ◽  
Stevia Rebaudiana Bertoni ◽  
Rich Material

Summary Stevia is a plant attracting attention due to its capability to synthesize a group of chemical compounds with sweet taste, i.e. steviol glycosides. Steviol glycosides are successfully applied as a natural sweetener, and some of them have also therapeutic properties. This paper presents available information on the use of stevia plant tissue cultures with the focus on their potential application in food industry. Detailed analysis was done concerning the research employing in vitro culture techniques and the use of them in biosynthesis of secondary metabolites of high importance for the food industry. Both established achievements and most recent publications on stevia were used for assessment of practical applications of the aforementioned techniques and prospects for their development.

The effect of the elicitors on the steviol glycosides biosynthesis pathway in Stevia rebaudiana

2019 ◽  
Vol 46 (9) ◽  
pp. 787 ◽  
Author(s):  
Hourieh Tavakoli ◽  
Nasibeh Tavakoli ◽  
Foad Moradi
Keyword(s):  
Salicylic Acid ◽  
Secondary Metabolites ◽  
Methyl Jasmonate ◽  
Biosynthetic Pathway ◽  
Stevia Rebaudiana ◽  
Sweet Taste ◽  
Steviol Glycosides ◽  
Biosynthesis Pathway ◽  
Stevia Rebaudiana Bertoni ◽  
Kaurenoic Acid

Stevia rebaudiana Bertoni has been promoted for having sweet leaves as well as pharmaceutical and industrial properties. The sweet taste of Stevia leaves is due to the presence of steviol glycosides (a group of diterpene glycosides) found in a small number of plants. In the biosynthetic pathway of steviol glycosides (SGs), 15 enzymes that express the genes are associated with these enzymes under the influence of the elicitors. Due to the individuality of the stevia and few studies on the biosynthesis pathway of SGs, this paper attempted to investigate the effects of some of the elicitors, including methyl jasmonate (MeJA), salicylic acid (SA), auxins (Aux), cytokinins (CKs), gibberellins (GAs) and its inhibitors including paclobutrazol (BPZ) and chloroquate (CCC)), on the responsible genes for the biosynthesis of SGs. Some of these elicitors, including MeJA, SA and GA have great potential in increasing secondary metabolites. Moreover, the biosynthetic pathway of GAs and SGs are shared till ent-kaurenoic acid (ent-KA) biosynthesis, which raises the question of whether this hormone and its inhibitors are effective in the SGs biosynthesis.

scholarly journals β-Glucosidase and β-Galactosidase-Mediated Transglycosylation of Steviol Glycosides Utilizing Industrial Byproducts

2021 ◽  
Vol 9 ◽  
Author(s):  
Anastasia Zerva ◽  
Koar Chorozian ◽  
Anastasia S. Kritikou ◽  
Nikolaos S. Thomaidis ◽  
Evangelos Topakas
Keyword(s):  
Low Cost ◽  
Stevia Rebaudiana ◽  
Cost Effective ◽  
Sweet Taste ◽  
Steviol Glycosides ◽  
Rebaudioside A ◽  
Glycosyl Hydrolases ◽  
Maximum Conversion ◽  
Acid Whey ◽  
Industrial Byproducts

Stevia rebaudiana Bertoni is a plant cultivated worldwide due to its use as a sweetener. The sweet taste of stevia is attributed to its numerous steviol glycosides, however, their use is still limited, due to their bitter aftertaste. The transglycosylation of steviol glycosides, aiming at the improvement of their taste, has been reported for many enzymes, however, glycosyl hydrolases are not extensively studied in this respect. In the present study, a β-glucosidase, MtBgl3a, and a β-galactosidase, TtbGal1, have been applied in the transglycosylation of two steviol glycosides, stevioside and rebaudioside A. The maximum conversion yields were 34.6 and 33.1% for stevioside, while 25.6 and 37.6% were obtained for rebaudioside A conversion by MtBgl3a and TtbGal1, respectively. Low-cost industrial byproducts were employed as sugar donors, such as cellulose hydrolyzate and acid whey for TtbGal1- and MtBgl3a- mediated bioconversion, respectively. LC-HRMS analysis identified the formation of mono- and di- glycosylated products from stevioside and rebaudioside A. Overall, the results of the present work indicate that both biocatalysts can be exploited for the design of a cost-effective process for the modification of steviol glycosides.

scholarly journals Induksi mutasi Stevia rebaudiana dengan perendaman kolkisin secara in vitro (Induced mutation of Stevia rebaudiana through colchicine soaking in vitro)

2018 ◽  
Vol 86 (1) ◽  
Author(s):  
Masna Maya SINTA ◽  
Ni Made Armini WIENDI ◽  
Syarifah Iis AISYAH
Keyword(s):  
Genetic Diversity ◽  
Sugar Industry ◽  
Stevia Rebaudiana ◽  
Dry Weight ◽  
Steviol Glycosides ◽  
Fresh Weight ◽  
Stomata Density ◽  
Chloroplast Number ◽  
Stomata Size

Stevia rebaudiana Bert. is a plant producing steviol glycosides that have 200-300 times sweeter than sucrose. These steviol glycosides are produced in the leaves and then spread to all parts of the plant including stems. The use of superior stevia planting material is important for stevia sugar industry. One of the stevia breeding programme is to increase genetic diversity through colchicine soaking to produce polyploid plants. Polyploid plants usually have higher vigor than diploid plants. The purpose of this research was to induce genetic diversity of stevia through colchicine soaking in vitro. Single nodes of sterile stevia clone BS were soaked in colchicine at the concentration of 0.01; 0.02; 0.04; 0.08 and 0.1% for 48 and 72 hours, and in sterile aquadest as a control. Plantlet subcultures were done until MV4 (mutant vegetative 4). Putative mutants were observed by plantlet vigor and stomata analyses on MV5. Vigor of plantlets was observed by counting the number of leaves, nodes, roots, fresh weight and dry weight of the plantlet. Stomata analysis was performed by calculating stomata density, stomata size and chloroplast number in stomata guard cells. Results showed that colchicine soaking treatment increased significantly fresh weight and dry weight of putative mutants. Colchicine soaking treatment increased chloroplast number on stomata guard cell and stomata size, but decreased stomata density. Stevia soaked in colchicine for 48 hours at concentration 0.01-0.04% produce putative mutants with high chromosome numbers. [Key words: poliploidy, stomata, chloroplast, mutant]AbstrakStevia rebaudiana Bert. merupakan tanaman penghasil glikosida steviol yang memiliki tingkat kemanisan 200-300 kali lebih tinggi dibandingkan sukrosa. Glikosida steviol ini diproduksi di daun yang kemudian disalurkan ke bagian tanaman lainnya termasuk batang. Penggunaan klon terbaik stevia merupakan salah satu kunci penting keberhasilan industri gula stevia. Salah satu program pemuliaan tanaman stevia adalah meningkatkan keragaman tanaman melalui mutasi dengan kolkisin sehingga menghasilkan tanaman poliploid. Tanaman poliploid umumnya memiliki vigor lebih baik dibandingkan tanaman diploid. Tujuan dari penelitian ini adalah untuk meningkatkan keragaman stevia melalui peren-daman kolkisin in vitro. Buku tunggal steril stevia klon BS direndam dalam kolkisin dengan konsentrasi 0,01; 0,02; 0,04; 0,08 dan 0,1% selama 48 dan 72 jam dengan perendaman dalam air steril sebagai kontrol. Sub kultur dilakukan hingga MV4 (mutan vegetatif 4). Pengamatan mutan putatif dilakukan meliputi analisis morfologi dan stomata pada MV5.  Analisis morfologi dilakukan dengan mengamati jumlah daun, buku, akar, bobot basah serta bobot kering planlet. Analisis stomata dilakukan dengan menghitung kerapatan stomata, ukuran stomata serta jumlah kloroplas pada sel penjaga stomata. Hasil menunjukkan bahwa perendaman stevia pada kolkisin meningkatkan bobot basah serta bobot kering stevia in vitro. Perlakuan perendaman kolkisin meningkatkan jumlah kloroplas pada sel penjaga stomata serta ukuran stomata namun menurunkan kerapatan stomata. Perendaman stevia selama 48 jam pada konsentrasi kolkisin 0,01-0,04% menghasilkan mutan putatif dengan jumlah kromosom tertinggi.[Kata kunci: poliploidi, stomata, kloroplas, mutan]

Sign in / Sign up

Export Citation Format

Share Document