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The genus Guizotia belongs to the tribe Heliantheae in the family Asteraceae. It has been placed under different subtribes. The genus has its center of origin, distribution and genetic diversity in Ethiopia, where G. abyssinica (niger) has been domesticated. Amplified Fragment Length Polymorphism (AFLP), Random Amplified Polymorphic DNA (RAPD) and...
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... from the rest of the taxa (Baagøe, 1974). G. jacksonni is a creeping perennial herb with sparsely branching habit grown within an altitudinal range of 2200-3700 m, endemic to Aberdares, Mt. Kenya and Mt. Elgon in Kenya and Uganda (Baagøe, 1974). Its creeping habit and solitary heads make it distinct from the other taxa. G. scabra ssp. scabra (Fig. 3) is a perennial, course, densely scabrous plant with stiff leaves, distributed, as part of natural vegetations, in East Africa, Cameron and Nigerian highlands, commonly within an altitudinal range of 1100-2700 m (Baagøe, 1974;Hiremath & Murthy, 1986). According to Baagøe (1974), it is the most variable taxon of the genus ...
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... Noug (Guizotia abyssinica) is an edible oilseed crop indigenous to Ethiopia, where it was originated, domesticated and genetically diversified. It is an annual diploid crop with 2n = 30 chromosomes (Dagne, 1994) exhibiting a strict outcrossing reproductive mechanism with honeybees as major pollinators due to its homomorphic self-incompatibility (Geleta et al., 2002;Geleta, 2007;Geleta and Bryngelsson, 2010). It is among major edible oilseed crops grown in Ethiopia, both in terms of acreage and production volume, where 26% of the produce is consumed locally (Geleta and Ortiz, 2013; Ethiopian Institute of Agricultural Research [EIAR], 2017). ...
Genomic resources and tools are essential for improving crops and conserving their genetic resources. Guizotia abyssinica (noug), an outcrossing edible oilseed crop, has highly limited genomic resources. Hence, RNA-Seq based transcriptome sequencing of 30 noug genotypes was performed to generate novel genomic resources and assess their usefulness. The genotypes include self-compatible and self-incompatible types, which differ in maturity time, photoperiod sensitivity, or oil content and quality. RNA-Seq was performed on Illumina HiSeq 2500 platform, and the transcript was reconstructed de novo, resulting in 409,309 unigenes. The unigenes were characterized for simple sequence repeats (SSRs), and served as a reference for single nucleotide polymorphism (SNP) calling. In total, 40,776 SSRs were identified in 35,639 of the 409,309 unigenes. Of these, mono, di, tri, tetra, penta and hexanucleotide repeats accounted for 55.4, 20.8, 21.1, 2.3, 0.2, and 0.2%, respectively. The average G+C content of the unigenes and their SSRs were 40 and 22.1%, respectively. The vast majority of mononucleotide repeat SSRs (97%) were of the A/T type. AG/CT and CCA/TGG were the most frequent di and trinucleotide repeat SSRs. A different number of single nucleotide polymorphism (SNP) loci were discovered in each genotype, of which 1,687 were common to all 30 genotypes and 5,531 to 28 of them. The mean observed heterozygosity of the 5,531 SNPs was 0.22; 19.4% of them had polymorphism information content above 0.30 while 17.2% deviated significantly from Hardy-Weinberg equilibrium (P < 0.05). In both cluster and principal coordinate analyses, the genotypes were grouped into four major clusters. In terms of population structure, the genotypes are best represented by three genetic populations, with significant admixture within each. Genetic similarity between self-compatible genotypes was higher, due to the narrow genetic basis, than that between self-incompatible genotypes. The genotypes that shared desirable characteristics, such as early maturity, and high oil content were found to be genetically diverse, and hence superior cultivars with multiple desirable traits can be developed through crossbreeding. The genomic resources developed in this study are vital for advancing research in noug, such as genetic linkage mapping and genome-wide association studies, which could lead to genomic-led breeding.
... The crop has high genetic diversity, particularly in Ethiopia [13], where it has been domesticated [14]. Geleta [15] and Geleta et al. [16] reported the genetic diversity of 70 Ethiopian noug collections using random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) markers and revealed the presence of higher genetic diversity within populations than among populations, which suggests wide genetic basis for noug improvement. However, its seed yield remains low, with national average productivity of about 1.1 t ha −1 , [12] with only a slight increase in 2018/2019 cropping season [12] despite breeding efforts to increase seed yield. ...
... The clustering pattern based on quantitative traits was somewhat different from that of qualitative traits suggesting a poor correlation between the two groups of traits. Such difference in clustering pattern of different Guizotia species and populations was also observed in molecular markers based studies (Random amplified polymorphic DNA vs Amplified Fragment Length Polymorphism) [15,35]. A recent study using transcriptome based SNP markers revealed a weak population structure in noug grown in Ethiopia due to population admixture, which is mainly a result of strong gene flow between populations via pollen and a gradual nation-wide germplasm exchange [36]. ...
Noug (Guizotia abyssinica) is an outcrossing oilseed crop that serves as a source of edible oil and other nutrients although its seed yield is generally low. The analysis of agro-morphological traits in relation to seed and oil yields is important for improving the productivity of this crop. The present study aimed at assessing the variation and heritability of quantitative (10) and qualitative (6) traits in noug based on 60 landrace accessions collected from wide geographic area in Ethiopia. The field trial was conducted at two sites in Ethiopia using a square lattice design. The analysis of variance revealed significant variation (p < 0.05) among these accessions. The highest broad-sense heritability (H2) was recorded for days to 10% flowering (DTF10; 85.4%), whereas number of capitula per plant (NCPP) and number of seeds per capitulum (NSPC) showed medium heritability (H2 = 38.5% and 31.6%, respectively). NCPP and NSPC showed a highly significant (p < 0.01) positive and negative genotypic correlation with days to flowering, respectively. These three traits showed very low genotypic coefficient of variation (
... In addition, the seeds are also used for making chatni, pickles and used as condiments (Geleta et al. 2007; Patil et al. 2013). This crop is highly-priced because of its edible oil containing useful and rare polyunsaturated fatty acids such as omega-3 and omega-9 fatty acids (linoleic and oleic acids). ...
Agronomic traits improvement in crop plant can be accomplished by induction of polyploidy. Niger ( Guizotia abyssinica (L.f.) Cass.) is one of the important edible oil yielding diploid crop (2n = 30). In the present study, the tetraploidization in Niger plants was achieved by treating apical portion of in vitro raised shoots with colchicine and their confirmation by chromosome counting and flow cytometry. The in vitro shoots were raised from leaf explants on MS medium supplemented with 1.0 mg/l BAP (6-benzylaminopurine). The survival and nature of growth of treated shoots was variable with colchicine concentration (0.0, 0.005, 0.01, 0.02, 0.03, and 0.04%) and exposure time (4, 8, 12, and 16 h). The maximum tetraploid induction ratio was recorded with 0.02% colchicine treatment for 8 h which yielded 38.4% tetraploids. The chromosome number in root cells of tetraploid plantlets was 2n=4x=60 and the DNA content in leaf cells was 10.34 pg which was double to the diploid plant (4.70 pg) cells. In addition, there was significant difference exist in leaf characteristics of diploid and tetraploid plantlets. Compared to diploid plantlets, the tetraploid plantlets showed larger leaves, larger stomatal size, low stomatal index, larger capitula, larger seeds, and a greater number of seeds per capitula. The oil content in seeds was higher and associated with altered fatty acid profile. The results demonstrated that the tetraploid plantlets obtained in this study exhibited some superior agronomical traits (as mentioned above) compared to diploid. The developed protocol and produced tetraploid plantlets will open the new door in improvement of edible oil yielding crop Guizotia abyssinica (L.f.) Cass.
... RAPD, ISSR, AFLP and microsatellite have proven effective in determining genetic variation of different genus within Asteraceae (Sehgal and Raina, 2005;Portis et al., 2005). As per as molecular aspects of genus Acmella is concerned, there are very few literature available to date such as optimization of DNA isolation and ISSR studies for six species of Acmella (Geleta, 2007), and use of RAPD and ISSR markers for evaluation of the genetic fidelity amongst regenerants of Spilanthes calva DC, a synonym of A. paniculata (Lavanya et al., 2014). ...
... La maladie causée par cet agent pathogène correspondà l'une des principales maladies du nyger, avec celle causée par l'agent pathogène fongique, Alternaria sp. (Geleta, 2007). En 2005, cette maladieétait caractérisée comme sévère en Ethiopie et moins importante en Inde (Saharan et al. 2005). ...
Comprendre l’émergence des maladies dans les agroécosystèmes nécessite d’étudier l’histoire évolutive des populations bactériennes associées aux plantes. L’objectif de ce travail était de déterminer les évènements évolutifsconduisant à l’émergence des lignées pathogènes ou pathovars dans l’espèce Xanthomonas arboricola. Une analyse de génétique des populations a été menée sur un panel de souches phytopathogènes et commensales et complétée par l’inférence des gains et pertes de facteurs de virulence. Cette espèce possède une structure de population épidémique ; les clones épidémiques ont émergé suite à l’acquisition de facteurs de virulence à partir d’un fond recombinant de souches commensales. Une analyse de génomique des populations et la reconstruction de scénarios de divergence entre ces clones et le réseau de souches recombinantes, a montré la persistance d’un flux de gènes asymétrique entre ces deux groupes, dans le sens souches pathogènes vers souches commensales. Enfin, l’histoire évolutive du principal facteur de virulence des Xanthomonas, le système de sécrétion de type 3, a été retracée au sein du genre, et a montré que celui-ci avait été acquis ancestralement puis perdu dans certaines souches commensales. En conclusion, l’ancêtre commun de X. arboricola possédait des facteurs de virulence et au sein des souches commensales, certaines ont perdu ces facteurs, tandis que d’autres ont conservé le répertoire ancestral. Ces dernières diffèrent peu de certains agents pathogènes, et pourraient représenter un risque pour de nouvelles émergences. Des travaux de génomique fonctionnelle permettraient de valider ces hypothèses.
... Noug has been described as semidomesticated (Dempewolf et al. 2008); the crop is self-incompatible and highly branched, and flowering heads and seeds are less than one-tenth the size of sunflower, its closest oil-seed crop relative (Funk et al. 2009). Hence, unlike sunflower, noug does not exhibit strong signs of artificial selection and bears much greater resemblance to its wild relatives (Geleta 2007) than does sunflower to its wild relative. Despite their phylogenetic proximity within the Compositae, sunflower has responded to human selection pressure quite differently from noug; cultivated sunflowers, unlike their wild progenitors, are single-stemmed and often single-headed, do not shatter, and have much larger seeds (Burke et al. 2002). ...
... ex Walp.) J.Baagøe is thought to be its progenitor (Hiremath and Murthy 1988;Dagne 1994;Geleta 2007). As previously has been shown, and we confirm in this study, Guizotia scabra ssp. ...
... As previously has been shown, and we confirm in this study, Guizotia scabra ssp. schimperii has smaller seeds than noug (Geleta 2007) but is also multibranched, shatters in the field, and exhibits differential maturity. It is a common and widespread species in many parts of Ethiopia, providing ample opportunity for gene flow between the two species . ...
Noug (Guizotia abyssinica) is a semi-domesticated oil-seed crop, which is primarily cultivated in Ethiopia. Unlike its closest crop relative, sunflower, noug has small seeds, small flowering heads, many branches, many flowering heads, indeterminate flowering, and it shatters in the field. Here we conducted common garden studies and microsatellite analyses of genetic variation to test whether high levels of crop-wild gene flow and/or unfavorable phenotypic correlations have hindered noug domestication. With the exception of one population, analyses of microsatellite variation failed to detect substantial recent admixture between noug and its wild progenitor. Likewise, only very weak correlations were found between seed mass and the number or size of flowering heads. Thus, noug's ‘atypical’ domestication syndrome does not seem to be a consequence of recent introgression or unfavorable phenotypic correlations. Nonetheless, our data do reveal evidence of local adaptation of noug cultivars to different precipitation regimes, as well as high levels of phenotypic plasticity, which may permit reasonable yields under diverse environmental conditions. Why noug has not been fully domesticated remains a mystery, but perhaps early farmers selected for resilience to episodic drought or untended environments rather than larger seeds. Domestication may also have been slowed by noug's outcrossing mating system.This article is protected by copyright. All rights reserved.
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http://onlinelibrary.wiley.com/doi/10.1111/eva.12256/full
... This implies that each population has unique genetic properties and is a significant pool for conservation and breeding. About 75 % of the total genetic variation in Ethiopian niger is found within populations (Geleta 2007), suggesting that several genotypes of interest could potentially be found within a single population. The level of genetic variation within populations is not associated with location, altitude and extent of cultivation (Geleta 2007), which makes niger suitable for adaptation to diverse environmental conditions. ...
... About 75 % of the total genetic variation in Ethiopian niger is found within populations (Geleta 2007), suggesting that several genotypes of interest could potentially be found within a single population. The level of genetic variation within populations is not associated with location, altitude and extent of cultivation (Geleta 2007), which makes niger suitable for adaptation to diverse environmental conditions. These studies also revealed a significant regional differentiation among populations. ...
Niger (noug; Guizotia abyssinica) is an economically important edible oilseed crop. This review sought to demonstrate the significance of niger for sustainable food security in Ethiopia, where it is produced exclusively by smallholders. In addition to its edible oil, niger seed is an important source of proteins, carbohydrates, vitamins and fiber that significantly contribute to the human diet. The crop has a wide genetic basis that is reflected in the form of a high variation in desirable traits, including seed yield, seed oil content, seed oil quality and photoperiod sensitivity. However, the wealth of niger genetic diversity has so far remained largely unexploited and research efforts have not yet yielded satisfactory results in the form of new and superior cultivars. The recent molecular and nutritional quality studies coupled with pre-breeding work have opened up new opportunities for the improvement of niger. A high yielding niger cultivars with oil content of up to 60 % and/or oleic acid content of up to 70 % can easily be bred based on Ethiopian niger gene pool through the combined use of novel genomic tools, traditional breeding and farmer-participatory approaches. The improvement of niger will have a significant contribution towards Ethiopia’s food security and sustainable development in general and self-sufficiency in edible oil in particular. Overall, an investment in the niger improvement programs will likely be of benefit far beyond Ethiopia’s borders and could potentially lead to the expansion of the crop outside the regions where it is currently grown.
... The chloroplast genome is useful in providing information on the inference of the evolutionary patterns and processes in plants (Raubeson and Jansen, 2005). The genome has, either solely or combined with other genomes, been widely used for inferring phylogenetic relationships of different taxa, including Hordeum, Triticum and Aegilops (Gielly and Taberlet, 1994), Guizotia (Geleta, 2007), Solanaceae (Melotto-Passarin et al., 2008) and Sorghum (Dillon et al., 2007). The non-coding chloroplast regions are phylogenetically more informative than the coding regions at lower taxonomic levels because they are under less functional constraints and evolve rapidly (Gielly and Taberlet, 1994). ...
Wild Sorghum species provide novel traits for both biotic and abiotic stress resistance and yield for the improvement of cultivated sorghum. A better understanding of the phylogeny in the genus Sorghum will enhance use of the valuable agronomic traits found in wild sorghum. METHODS Four regions of chloroplast DNA (cpDNA; psbZ-trnG, trnY-trnD, trnY-psbM and trnT-trnL) and the internal transcribed spacer (ITS) of nuclear ribosomal DNA were used to analyse the phylogeny of sorghum based on maximum-parsimony analyses.
Parsimony analyses of the ITS and cpDNA regions as separate or combined sequence datasets formed trees with strong bootstrap support with two lineages: the Eu-sorghum species S. laxiflorum and S. macrospermum in one and Stiposorghum and Para-sorghum in the other. Within Eu-sorghum, S. bicolor-3, -11 and -14 originating from southern Africa form a distinct clade. S. bicolor-2, originally from Yemen, is distantly related to other S. bicolor accessions.
Eu-sorghum species are more closely related to S. macrospermum and S. laxiflorum than to any other Australian wild Sorghum species. S. macrospermum and S. laxiflorum are so closely related that it is inappropriate to classify them in separate sections. S. almum is closely associated with S. bicolor, suggesting that the latter is the maternal parent of the former given that cpDNA is maternally inherited in angiosperms. S. bicolor-3, -11 and -14, from southern Africa, are closely related to each other but distantly related to S. bicolor-2.
... The occurrence of genetic variability between and within individuals, within population and between cultivars in cultivated species occurred by mutation, introgression, recombination, adaptation to new environment, and selection which occurs continually (Geleta et al., 2007). Genetic diversity within cultivated and wild plants is important to prevent some problems associated with cultivation failure. ...
Indonesia, and in order evaluate genetics diversity of mangosteen and their close relatives, we employed isoenzyme and AFLP marker on 13 accessions of mangosteen and their close relatives. Isoenzyme marker using four enzyme systemsproduced 25 bands and 88% out of them were polymorphic and elucidate genetic variability at similarity level ranged between 0.38-0.89. AFLP markers with three primer system produced 220 polymorphic bands and revealed genetic variability at similarity level ranged between 0.38-0.89 successfully produced high polymorphism bands and elucidates genetic variability at similarity coefficient ranged between 0.21-0.77. Both markers exhibited similar clustering pattern, and group successfully G. mangostana accessions in one clustering group. Furthermore G. malaccensis and G. porrecta consistently showed closer genetic relationship to G. mangostana clustering group in both markers, in comparison to G. hombroniana, which implies the assumption they may be the progenitor of G. mangostana, and should be reviewed with more accurate data.© 2009 Biodiversitas, Journal of Biological DiversityKey words: genetic diversity, mangosteen, isozymes, AFLP.
... Overall, the genetic distance among populations may or may not correlate with the geographical distance between them in some species depending on natural and artificial factors involved in shaping the population genetic structure of the species (Stankiewicz et al., 2001). For example, the positive correlation between genetic distance and geographical regions was found in niger populations (Geleta, 2007) but not in safflower (Khan et al., 2009). 31 4.4 Phenotype evaluation and phenotypic relationship of sesame varieties from different origins (paper III) ...
