Phenotypic diversity in tetraploid wheats collected from Bale and Wello regions of Ethiopia

2005 ◽  
Vol 3 (1) ◽  
pp. 35-43 ◽  
Author(s):  
Firdissa Eticha ◽  
Endeshaw Bekele ◽  
Getachew Belay ◽  
Andreas Börner
Keyword(s):  
Phenotypic Diversity ◽  
Diversity Index ◽  
Drastic Change ◽  
Seed Colour ◽  
Spike Density ◽  
Qualitative Traits ◽  
Tetraploid Wheats ◽  
Glume Colour ◽  
Regional Basis ◽  
Different Levels

The phenotypic diversity of 32 landrace populations of tetraploid wheats originating from the Bale and Wello regions of Ethiopia was studied. Eight heritable qualitative traits (glume hairiness, glume colour, awnedness, awn length, beak awn, awn colour, spike density, seed colour) were measured on 2453 individual plants (45–110 plants per landrace). The frequencies of each phenotypic class were used to estimate and analyse the diversity at different levels (population, altitude, region). Beak awn and seed colour showed the highest diversity index, and glume hairiness the lowest. Glume hairiness, glume colour, beak awn and awn colour were regionally variable, while gradients across altitude were observed for glume hairiness, glume colour and beak awn. Variation was, however, largely due to the differences in the level of the different characters within populations. On a regional basis, a higher mean diversity index was observed for materials from Wello than from Bale. No drastic change in the overall diversity between these collections and those analysed in the 1970s was evident.

scholarly journals Exploring morpho-physiological profiles of a collection of tomato (Solanum lycopersicum) germplasm using multivariate statistics

2020 ◽  
Vol 18 (2) ◽  
pp. 88-97
Author(s):  
Ifigeneia Mellidou ◽  
Konstantinos Krommydas ◽  
Irini Nianiou-Obeidat ◽  
Georgia Ouzounidou ◽  
Apostolos Kalivas ◽  
...  
Keyword(s):  
Solanum Lycopersicum ◽  
Phenotypic Diversity ◽  
Diversity Index ◽  
Total Yield ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Fruit Shape ◽  
Qualitative Traits ◽  
Germplasm Collections ◽  
Wide Range

AbstractA selection of tomato (Solanum lycopersicum L.) genotypes with diverse origin and breeding history including 33 landraces, eight modern varieties and two commercial hybrids has been characterized using a set of 25 qualitative descriptors and six quantitative traits. A wide range of variation was evident for the majority of traits, highlighting their utility for characterizing tomato germplasm collections. A plethora of qualitative traits including type of leaf blade, depression and ribbing at peduncle end, fruit shape at blossom end, number of locules and flowering time, as well as measured traits with economic importance such as fruit fresh weight, firmness and total yield per plant, were found to be highly variable within the collection, with a diversity index greater than 0.8. Strong correlations were detected among several traits related to fruit yield and quality. Two-dimensional principal component analysis as well as the unsupervised hierarchical clustering grouped genotypes according to their phenotypic resemblance and morphological characteristics to a great extent. Landraces from different origins were scattered across the whole variation spectrum of PC1 and PC2. A set of six qualitative traits could efficiently discriminate cultivars in PCA (explaining 75% of total variation), suggesting that it can serve as a valuable breeding tool for the germplasm characterization. The evaluation of the phenotypic diversity in the collection as well as the identification of traits that contribute most to heterogeneity have important implications for establishing core collections with high diversity, as well as designing breeding schemes across the Mediterranean basin.

scholarly journals Morphological Characterization of 22 Accessions of Pigeon Pea [Cajanus cajan (L) Millsp.]

2020 ◽  
pp. 20-28
Author(s):  
Kemi Adegboyegun ◽  
Fidelis Etuh Okpanachi ◽  
Kufre Ededet Akpanikot
Keyword(s):  
Cajanus Cajan ◽  
Quantitative Traits ◽  
Phenotypic Diversity ◽  
Pigeon Pea ◽  
Colour Pattern ◽  
Small Scale ◽  
Phenotypic Traits ◽  
Central Research ◽  
Seed Colour ◽  
Qualitative Traits

Pigeon pea (Cajanus cajan [L] Millsp.) is a multipurpose legume crop that provides food fodder and wood for small scale farmers. However, it remains one of the underutilised crops with limited research done so far for the crop diversification and improvement. In this study, the phenotypic diversity of 22 accessions of pigeon pea was evaluated. The Seeds were collected from ICRISAT Niamey, Niger. The study was carried out at the biological garden and at the central research laboratory of the University of Lagos. Viability test was done on the collected seeds before planting in a polythene pot. The phenotypic traits measured include both the quantitative and qualitative traits. Analysis of variance revealed significant differences among accessions for all quantitative traits, except the seed length, seed breadth, seed thickness and the number of germinated seeds per pot. For qualitative traits, seed colour pattern and primary seed colour were diverse, other qualitative traits measured in this study showed moderate level of variation. The results for cluster analysis for both qualitative and quantitative traits grouped the accessions into two major clusters. In all the dendrograms, accessions ISC 147, ISC 24, ISC 157 and ISC 185 were varied and showed good performance for morphological traits analysed as well. The result of the phenotypic diversity observed in this study can help in parental selection for subsequent plant breeding.

scholarly journals Genetic Diversity among Sugarcane Genotypes Based on Qualitative Traits

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Esayas Tena Gashaw ◽  
Firew Mekbib ◽  
Amsalu Ayana
Keyword(s):  
Genetic Diversity ◽  
Phenotypic Diversity ◽  
Diversity Index ◽  
Morphological Diversity ◽  
Germplasm Resources ◽  
Frequency Distributions ◽  
Qualitative Traits ◽  
Sugarcane Crop ◽  
Future Improvement ◽  
Sugarcane Germplasm

The study was conducted during 2012/2013 at Wonji Sugar Estate, Ethiopia, to estimate the extent of morphological diversity among sugarcane germplasm based on 16 qualitative traits. Four hundred sugarcane genotypes grouped in 20 locations were considered. Phenotypic frequency distributions of the characters were analyzed and Shannon-Weaver diversity index (H′) was computed using the phenotypic frequencies. Results indicated that the variation inH′within locations was larger than the diversity observed between locations. The value ofH′for all sample genotypes ranged from 0.43 to 0.98 with a mean of 0.87. Considerable phenotypic diversity was observed among the germplasm studied. This information can be used for establishing proper identity of the accessions, strategic conservation of these germplasm resources, and future improvement work of the sugarcane crop. This is the first study to report phenotypic diversity of local and exotic sugarcane genotypes in Ethiopia.

Scandinavian mutation research during the past 90 years - a historical review.

2021 ◽  
pp. 10-23
Author(s):  
Udda Lundqvist
Keyword(s):  
Phenotypic Diversity ◽  
Historical Review ◽  
Chemical Mutagenesis ◽  
Induced Mutations ◽  
Spike Density ◽  
Early Maturity ◽  
Breeding Programmes ◽  
The Difference ◽  
Effects Of Radiation ◽  
Wax Coating

Abstract In 1928, the Swedish geneticists Herman Nilsson-Ehle and Åke Gustafsson started to act on their own ideas with the first experiments with induced mutations using diploid barley. They started with X-rays and UV irradiation. Very soon the first chlorophyll mutations were obtained and followed by the first 'vital' mutations Erectoides (ert) (Franckowiak and Lundqvist, 2001). Several other valuable mutations were identified as early maturity, high yielding, lodging resistant and characters with altered plant architecture. The experiments expanded to include other different types of irradiation, followed by chemical mutagenesis starting with mustard gas and concluding with sodium azide. The research brought a wealth of observations of general biological importance, such as the physiological effects of radiation as well as the difference in the mutation spectrum with respect to mutagens. This research was non-commercial, even if some mutants have become of important agronomic value. It peaked in activity during the 1950s to 1980s and, throughout, barley was the main experimental crop. About 12,000 different morphological and physiological mutants with a very broad phenotypic diversity were brought together and are incorporated in the Nordic Genetic Resource Centre (NordGen), Sweden. Several important mutant groups have been analysed in more detail genetically, with regard to mutagen specificity and gene cloning. These are: (i) early maturity mutants (Praematurum); (ii) six-rowed and intermedium-spike mutants; (iii) mutants affecting surface wax coating (Eceriferum); and (iv) mutants affecting rachis spike density (Erectoides). Some of these groups are presented in more detail in this review. Once work with induction of mutations began, it was evident that mutations should regularly be included in breeding programmes of crop plants. In Sweden, direct X-ray induced macro-mutants have been successfully released as cultivars, some of them having been used in combination breeding. Their importance for breeding is discussed in more detail.

scholarly journals Geographical patterns of phenotypic diversity and structure of Kenyan wild sorghum populations (Sorghum spp.) as an aid to germplasm collection and conservation strategy

2010 ◽  
Vol 8 (3) ◽  
pp. 217-224 ◽  
Author(s):  
Moses M. Muraya ◽  
Hartwig H. Geiger ◽  
Evans Mutegi ◽  
Ben M. Kanyenji ◽  
Fabrice Sagnard ◽  
...  
Keyword(s):  
Phenotypic Diversity ◽  
Diversity Index ◽  
Flag Leaf ◽  
Germplasm Collection ◽  
Principal Component ◽  
Conservation Strategy ◽  
Ex Situ ◽  
Regional Differentiation ◽  
Wild Sorghum ◽  
Geographical Patterns

Kenya lies within sorghum centre of diversity. However, information on the relative extent of diversity patterns within and among genetically defined groups of distinct ecosystems is lacking. The objective was to assess the structure and phenotypic diversity of wild sorghum populations across a range of geographical and ecological conditions in the country. Sixty-two wild sorghum populations (30 individuals per population) sampled from four distinct sorghum growing regions of Kenya and covering different agroecologies were characterized for ten qualitative traits. Plant height, number of tillers, panicle sizes and flag leaf dimensions were also recorded. Frequencies of the phenotypic classes of each character were calculated. The Shannon diversity index (H′) was used to estimate the magnitude of diversity. Principal component analysis was used to differentiate populations within and between regions. Wild sorghum is widely distributed in Kenya, occurring in sympatric ranges with cultivated sorghum, and both have overlapping flowering windows. All characters considered displayed great phenotypic diversity. Pooled over characters within regions, the mean H′ ranged between 0.60 and 0.93 in Western and Coast regions, respectively. Wild sorghum was found to show a weak regional differentiation, probably reflecting the importance of seed-mediated gene flow in shaping the wild sorghum population structure. Trait distribution was variable among regions, but there was no conspicuous distribution of the traits studied in any given region. Spontaneous hybridization and introgression of genes from cultivated to wild sorghum seems to be likely, and may already have occurred for a long time, although undocumented. Implications for in situ and ex situ genetic resources conservation are discussed.

Diversity of Ethiopian tetraploid wheat germplasm: breeding opportunities for improving grain yield potential and quality traits

2009 ◽  
Vol 7 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Yifru Teklu ◽  
Karl Hammer
Keyword(s):  
Total Variation ◽  
Phenotypic Diversity ◽  
Diversity Index ◽  
Tetraploid Wheat ◽  
Principal Component ◽  
Diversity Indices ◽  
Yield Potential ◽  
Wheat Improvement ◽  
Geographical Regions ◽  
Diversity Studies

In this paper, Shannon–Weaver diversity indices were employed to examine the phenotypic diversity in 271 Ethiopian tetraploid wheat accessions in relation to characters, regions of origin and altitude. Moreover, review of genetic diversity studies in Ethiopian tetraploid wheat was made to explore breeding opportunities. The diversity index varied widely across regions. Among the four altitudinal classes, the highest (0.72) and lowest (0.61) mean diversity indices were observed in altitude classes II and IV, respectively. The diversity index (H′) showed that most traits are polymorphic. The partitioning of the total phenotypic diversity into within- and among-region diversity indicated that 71% of the total variation was attributed to the within-region diversity. Principal component analysis was computed to examine the regional and altitudinal patterns of variation. On regional bases, the first four axes, whose eigenvalues are greater than 1, explained about 82% of the observed phenotypic diversity in the 271 tetraploid wheat accessions. On altitudinal bases, however, only the first two principal components explained 89.7% of the total variation. In general, phenotypic diversity showed considerable differences for each trait in different geographical regions and altitudinal classes which could be utilized in wheat improvement programmes. Breeding opportunities and strategies are suggested.

WILD EMMER WHEAT IN JORDAN: III. A CORE COLLECTION

1997 ◽  
Vol 45 (1) ◽  
pp. 45-51
Author(s):  
A.A. Jaradat
Keyword(s):  
Core Collection ◽  
Phenotypic Diversity ◽  
Diversity Index ◽  
Triticum Dicoccoides ◽  
Sampling Procedure ◽  
Wild Emmer Wheat ◽  
Emmer Wheat ◽  
Wild Emmer ◽  
Multivariate Statistical ◽  
Percent Contribution

The germplasm base collection (BC) of wild emmer wheat,Triticum dicoccoides, from Jordan consists of over 2,000 accessions. Data on 10 quantitative and 8 qualitative traits were analyzed using multivariate statistical analysis procedures. A stratified and proportional sampling procedure was used to select 10 and 5% of the BC to form two core collections: CC10 and CC5, respectively. Phenotypic variation in the BC, as estimated by the phenotypic diversity index, hs,j, was unevenly distributed among accessions, among populations, and among ecogeographical regions. Moreover, its level differed significantly among and within quantitatively and qualitatively inherited traits. This characteristic led to successfully selecting a core collection which represents all levels of hierarchy in the base collection. Examination of the data for the same 18 traits in the BC, CC10, and CC5 indicated that CC10 and CC5 retained, on average, 86.0 and 74.3% of the variation in the BC, respectively. Percent discrete phenotypic classes, with frequency >0.10 (i.e., common widespread and common localized phenotypes). recovered in CC10 and CC5 were 79.6 and 51.5%, respectively. Results of hierarchical analyses of variance showed that percent contribution by traits to total variance in hs,j. estimates increased from 64.0% in the BC to 78.0% in CC10, and to 96.3% in CC5. Nevertheless, and as theoretically expected, CC10 was more efficient than CC5 in retaining the amount and composition of the variation originally found in the base collection.

scholarly journals Evaluation of the Genetic Variation of Cowpea Landraces (Vigna unguiculata) from Western Cameroon Using Qualitative Traits

2017 ◽  
Vol 9 (4) ◽  
pp. 508-514 ◽  
Author(s):  
Toscani NGOMPE-DEFFO ◽  
Eric Bertrand KOUAM ◽  
Honoré BEYEGUE-DJONKO ◽  
Mariette ANOUMAA
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Growth Habit ◽  
Diversity Index ◽  
Diversity Indices ◽  
Crop Species ◽  
Qualitative Trait ◽  
Qualitative Traits ◽  
Leaf Hairiness

Characterization of the genetic diversity and analysis of the genetic relationship between accessions of a crop species is a key step in breeding superior cultivars. The main objective of the hereby study was to determine the genetic variation between 30 cowpea accessions collected throughout the eight divisions of the Western Region of Cameroon using qualitative traits. Phenotypic variation of these accessions was evaluated using diversity indices and cluster analyses. A total of twenty qualitative traits were used for the study. Fifteen of them (75%) were polymorphic, displaying each at least two phenotypic classes. The monomorphic characters were growth pattern, leaf color, leaf hairiness, plant hairiness and pod hairiness, each with only one phenotypic class. Results showed a relatively significant level of genetic diversity among the studied cowpea accessions. Overall, the average of the observed and effective number of phenotypic classes per qualitative trait were Na = 2.350 and Ne = 1.828 respectively. The Nei’s genetic diversity and the Shannon weaver diversity index were He = 0.369, ranging from zero (monomorphic trait) to 0.655 (growth habit) and H’ = 0.609, ranging from zero (monomorphic trait) to 0.996 (seed crowding), respectively. The dendrogram constructed from the twenty qualitative traits revealed 05 accessions clusters with the number of accessions in each cluster varying from one to eleven. Information obtained from this study is likely be useful for future cowpea breeding program.

scholarly journals Assessing the Genetic Diversity and Population Structure of a Tunisian Melon (Cucumis melo L.) Collection Using Phenotypic Traits and SSR Molecular Markers

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1121
Author(s):  
Hela Chikh-Rouhou ◽  
Najla Mezghani ◽  
Sameh Mnasri ◽  
Neila Mezghani ◽  
Ana Garcés-Claver
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Phenotypic Diversity ◽  
Diversity Index ◽  
Polymorphic Information Content ◽  
Crop Improvement ◽  
Molecular Data ◽  
Mantel Test ◽  
Phenotypic Traits ◽  
Genetic Diversity And Structure

The assessment of genetic diversity and structure of a gene pool is a prerequisite for efficient organization, conservation, and utilization for crop improvement. This study evaluated the genetic diversity and population structure of 24 Tunisian melon accessions, by using 24 phenotypic traits and eight microsatellite (SSR) markers. A considerable phenotypic diversity among accessions was observed for many characters including those related to agronomical performance. All the microsatellites were polymorphic and detected 30 distinct alleles with a moderate (0.43) polymorphic information content. Shannon’s diversity index (0.82) showed a high degree of polymorphism between melon genotypes. The observed heterozygosity (0.10) was less than the expected heterozygosity (0.12), displaying a deficit in heterozygosity because of selection pressure. Molecular clustering and structure analyses based on SSRs separated melon accessions into fivegroups and showed an intermixed genetic structure between landraces and breeding lines belonging to the different botanical groups. Phenotypic clustering separated the accessions into two main clusters belonging to sweet and non-sweet melon; however, a more precise clustering among inodorus, cantalupensis, and reticulatus subgroups was obtained using combined phenotypic–molecular data. The discordance between phenotypic and molecular data was confirmed by a negative correlation (r = −0.16, p = 0.06) as revealed by the Mantel test. Despite these differences, both markers provided important information about the diversity of the melon germplasm, allowing the correct use of these accessions in future breeding programs. Together they provide a powerful tool for future agricultural and conservation tasks.

scholarly journals Characterization of Sorghum germplasm for various qualitative traits

2017 ◽  
Vol 9 (2) ◽  
pp. 1002-1007
Author(s):  
Rajani Verma ◽  
B. R. Ranwah ◽  
Baudh Bharti ◽  
Ramesh Kumar ◽  
Ram Kunwar ◽  
...  
Keyword(s):  
Grain Shape ◽  
Leaf Sheath ◽  
College Of Agriculture ◽  
Plant Vigour ◽  
Qualitative Traits ◽  
Glume Colour ◽  
Dark Green ◽  
Endosperm Texture ◽  
Sorghum Germplasm

Present study was performed to characterize 750 germplasm lines with 4 checks namely CSV17, CSV20, CSV27 and CSV21F for various qualitative traits of Sorghum. These 754 genotypes were sown in augmented RBD with 30 replications during Kharif 2014 at Instructional Farm, Rajasthan College of Agriculture, Udaipur. Majority of the accessions showed poor early plant vigour (40.2 %), dark green leaf (88.6 %), non- tan leaf sheath pigmentation (60 %), drooping leaves (100 %), white midrib colour (51.6 %), senescence (60 %), loose panicle density (31.5 %), elliptical panicle shape (66.5 %), straw glume colour (48.2 %), 3/4 glume coverage (42.9 %), absence of awns (59.5 %), creamy straw seed (39.9 %), oval grain shape (48.8 %), medium seed size (43.7 %), non-lustrous seed (62.0 %), intermediate endosperm texture (50.3 %) and bicolor race (49.6 %). Very good early plant vigour, tan type leaf sheath pigmentation, drooping leaf orientation, straw glume colour, ½ glume covering, oval grain shape, intermediate endosperm texture appeared in all the 4 check. The results of this study indicated that considerable genetic diversity exists among the sorghum accessions.

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