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The 17 Brazilian species of Adesmia DC were analysed, using 20 primers, with regard to their randomly amplified polymorphic DNA (RAPD) patterns. From a total of 357 individuals analysed, the 20 primers produced 2249 fragments with molecular sizes ranging from 200 to 2700 bp, 56% of which were polymorphic. Average intra-population genetic similarity, estimated by Jaccard's coefficient, ranged from 0.35 in A. araujoi to 0.80 in A. punctata. Mean intra-specific genetic similarity varied greatly among species, ranging from 0.19 for A. tristis to 0.89 for A. arillata. Mean genetic similarity among the species, estimated by Dice's coefficient, was 0.56. RAPD markers were efficient at separating all the accessions analysed. The results obtained generally agreed with the partition of genetic variability expected according to the mode of reproduction.
Gymnema sylvestre (Retz.) R. Br. ex Schult is a highly demanded antidiabetic medicinal herb native to India. There are no improved varieties available and the plant is still collected from the wild and therefore it is important to estimate the genetic variability and heritability parameters for devising appropriate crop improvement strategy. The present study was undertaken to assess the genetic variability, heritability, character association and path analysis for growth, yield and bioactive traits in 35 accessions of G. sylvestre collected from Indian South Peninsular region. Genetic variability parameters: genotypic variance, phenotypic variance, genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), broad-sense heritability, genetic advance and genetic advance as per cent over mean of yield and quality related characters were computed to understand the extent of variability present. High levels of GCV and PCV (>20%) were observed for most of the traits. Leaf length, leaf area, leaf yield and gymnemagenin content reported with high heritability (>60%) and genetic advance over mean (>30%) suggest that variation in these traits is influenced predominantly by the genetic factors making selection more effective in improving them. The correlation and path analysis studies highlighted the importance of selecting leaf length, leaf breadth, leaf area index, fresh leaf yield and gymnemagenin content for improving dry leaf yield of G. sylvestre. The study also identified promising morphotypes (IIHR-GS-27 and IIHR-GS-9) and chemotypes (IIHR-GS-44) which can be utilized for the commercial exploitation or can serve as pre-breeding materials in the crop improvement programmes.
Toxocara vitulorum is one of the deadliest parasite of buffalo calves in Bangladesh. This study was conducted to explore genetic variability within and among the T. vitulorum populations in buffalo calves of Bangladesh. Genomic DNA was extracted, ITS2, COX1 and NAD1 gene were amplified and sequenced. Distinct 29 ITS2, 21 unique NAD1 and 24 COX1 genotypes were detected among the T. vitulorum of different geographic regions. These three gene genotypes similarities ranged from 97 to 99%, when these were compared to best hit scoring T. vitulorum sequences retrieved from GenBank. A total of 12 and 6 unique haplotypes were detected for COX1 and NAD1 gene sequences. The average nucleotide and haplotype diversity for COX1 and NAD1 were 0.0931 & 0.89493 and 0.00658 & 0.77895 respectively and the recorded values were more dispersed than previously published values. The pairwise Nst values ranged from −0.050 to 0.602 and Fst from −0.050 to 0.600 between all the T. vitulorum genotypes indicated huge genetic differentiation which were reportedly higher than other published reports Fst values. This is the first report of T. vitulorum on the basis of COX1 gene in Bangladesh. The study findings will be helpful for further extensive epidemiological studies regarding anthelmintic resistance, control and prevention of T. vitulorum infection in buffalo calves.
Bitter vetch (Vicia ervilia (L.) Willd) is a promising legume, drought tolerant, mainly used in the Mediterranean area for its grains as a source of proteins in animal feed. However, it is an underused crop cultivated in marginal soils. Ecological, agro-morphological, and bromatological diversity evaluations were conducted to study its reintroduction potential. Seeds of seventeen ecotypes were collected in seventeen farms located in Northern Morocco in 2018. The cultivation was realised during the 2019 and 2020 growing seasons using a randomised complete block design with three replicates. Agro-morphological data were collected at the start of flowering, full flowering, and pod setting phenological stages. Yield component assessment and grain and straw bromatological characterisation were performed at maturity. The results indicated significant variations between ecotypes for almost all parameters and interesting results about yield (1 t ha–1) but lower protein content (22.9% of dry matter) compared to other ecotypes of the Mediterranean region. The estimated genetic parameters could emphasise the possibility of selecting highly productive and nutritive cultivars. However, interannual variations were also detected, making the selection of the ecotypes harder. No significant correlations were observed between agro-morphological and bromatological traits of grains and geographical distances. Multivariate analyses (principal component analysis and heatmap) clustered ecotypes into five groups, where the ecotypes included in the second cluster were the most interesting candidates for developing high-yielding and nutritive varieties. That is why this plant could be considered of interest, especially in these times of climate change.
Low phosphorus use efficiency (PUE) is one of the abiotic factors that hamper yield and production potential in chickpea (Cicer arietinum L.). Higher yield coupled with improved PUE can make this crop more adaptive and competitive to wide cropland area, especially on marginal soils having low-level phosphorus (P). To identify chickpea germplasm lines that assimilate phosphorus more efficiently under P-deficient soils, 288 diverse genotypes of chickpea belonging to reference set were evaluated for yield component traits and PUE under field conditions for two consecutive years at two phosphorus levels (low P – no phosphorus application and high P – phosphorus application at 40 kg/ha). Based on 2-year evaluation of data under high and low P soil conditions, we identified strong correlations for traits like number of primary and secondary branches, number of pods, biological yield and seed yield indicating that these traits can be used as proxy traits for PUE. ICC 6571 was the best performing genotype under low P conditions while ICC 6579 yielded maximum under high P regime. We report 16 genotypes namely ICC 1052, ICC 1083, ICC 1098, ICC 1161, ICC 2072, ICC 4418, ICC 4567, ICC 4991, ICC 5504, ICC 5639, ICC 7413, ICC 8350, ICC 9590, ICC 9702, ICC 11584 and ICC 13357 as phosphorus use efficient genotypes based on their better performance for yield and yield-contributing traits under low P compared to high P conditions. These genotypes can be exploited in future as potential donors for development of phosphorus use efficient chickpea cultivars.
A total of 108 diverse sorghum (Sorghum bicolor) accessions were characterized for quantitative and qualitative fodder-related traits and zonate leaf spot (ZLS) (Gloeocercospora sorghi) disease during two successive wet seasons of 2019 and 2020 in augmented randomized block design. The Shannon's diversity index and analysis of variance showed the existence of significant variability among qualitative and quantitative traits. K-mean clustering showed strong relationship between green fodder yield (GFY) and other yield-contributing traits. The dendrogram constructed based on morphological traits classified accessions into four diverse groups and most of genotype fall under cluster II. The principal component analysis bi-plot analysis showed a total variation of 68.96%, where GFY, stem weight per plant, panicle length and dry matter yield (DMY) contributed significantly. From the experimental results, three sorghum genotypes viz., IG-03-424, IG-01-436 and IG-03-438 were identified as promising for higher GFY (808.66 g/plant) and DMY (238.0 g/plant), respectively. Further, based on disease reactions under natural condition, five genotypes viz., EC-512397, EC512393, EC512394, EC512399 and IG-02-437 were identified as potential donor for resistance to ZLS disease. These selected lines could be used as promising sources for high biomass and disease resistance in forage sorghum breeding programme.
The true characterization of elite germplasm is of utmost importance for accelerating the crop breeding programme. The Indian dolichos bean [Lablab purpureus (L.) var. typicus Prain] has the potential to improve nutritional and food security. In the present investigation, a total of 21 genotypes of dolichos bean, comprising local collections mainly, along with one standard check (Kashi Sheetal) were evaluated in a complete randomized block design with three replications for two consecutive years, 2021–22 to 2022–23 for the perusal of the genetic variability. Analysis of variance revealed significant differences among all the genotypes for all the characters. PCV and GCV estimates revealed very little influence of environment on the expression of traits under study. High heritability (>90%) estimates coupled with high genetic advance as a percent of the mean were observed for flower attributes, pod length, average weight of 10 pods, pod yield and protein content. The principal component analysis revealed that the first two components cumulatively accounted for more than 50% of total variability. The present investigation revealed that the genotypes, RLBDL-S-8, RLBDL-S-14 and RLBDL-S-4-5 were stable across the years and genotype RLBDL-S-8 exhibited the highest yield potential, which can be used effectively in the development of high yielding varieties of dolichos bean in the Bundelkhand region. The study also revealed the presence of wide genetic variability in the studied local accessions which is a prerequisite for the genetic improvement of crop plants. High heritability and genetic advancement indicated the scope of selection in the crop improvement.
One of the most essential prerequisites in plant breeding is to have a maximum collection of germplasm materials with all sorts of variability. As a part of the programme under the All India Coordinated Research Projects on Spices, totally 196 germplasm accessions of small cardamom are being maintained as field gene bank repository at the Cardamom Research Station, Pampadumpara. Tropical evergreen forests of the Indian Western Ghats and Sri Lankan Central Highlands are recognized as the home of cardamom. The area and production of cardamom are maximum in Kerala followed by Karnataka and Tamil Nadu. Variations among the germplasm collections in morphological and biometrical characters as well as for yield have been studied and reported in this paper. Accessions with distinct morphological marker characters, such as compound panicle types, terminal panicle bearing, narrow leaf types, pink pseudostem types, dark green bold capsules with high-yield potential and biotic-stress tolerant types, are being evaluated and conserved in this repository. The assessment of genetic diversity is an essential prerequisite for undertaking crop breeding activities to evolve suitable area and region-specific variety. Sixty-seven cardamom accessions were studied for genetic diversity by evaluating 14 unique characters for 3 years (2016–2018). Almost all accessions have shown significant variability for most of the biometric and biotic stress characters. Results have indicated a greater magnitude of genetic diversity of small cardamom present among accessions representing whole evergreen tropical forest of the Western Ghats.
The present study evaluated the reproductive compatibility of Trichogramma pretiosum Riley, 1879, through an integrative approach using biological data and morphometry of three isofemale lines (isolines) collected from two geographical areas. These isolines differed in sequences of mitochondrial DNA and reproductive performance in the laboratory. The wasps used to initiate the isolines were collected in different environments: two lines from a Mediterranean climate in Irvine, California, USA, and one line from a tropical climate in Piracicaba, São Paulo, Brazil. Reproductive compatibility was studied by evaluating the sex ratio and number of adult offspring produced of all mating combinations between adults from these isolines. Morphometry was studied by measuring 26 taxonomically useful characters, followed by a multivariate analysis. For the allopatric matings among Brazilian and North American isolines, a low level of crossing incompatibility was recorded, in only one direction of the crosses; whereas the sympatric North American isolines were incompatible in both directions. Multivariate analysis of the morphometric data indicated no distinct groups, suggesting that despite the genetic and biological differences, the isofemale lines are morphologically similar.
Stylops ater is an endoparasite of the mining bee Andrena vaga with extreme sexual dimorphism and hypermetamorphosis. Its population structure, parasitization mode, genetic diversity and impact on host morphology were examined in nesting sites in Germany to better understand this highly specialized host–parasite interaction. The shift in host emergence due to stylopization was proven to be especially strong in A. vaga. Around 10% of bees hosted more than 1 Stylops, with at maximum 4. A trend in Stylops' preference for hosts of their own sex and a sex-specific position of extrusion from the host abdomen was found. Invasion of Andrena eggs by Stylops primary larvae was depicted for the first time. Cephalothoraces of female Stylops were smaller in male and pluristylopized hosts, likely due to lower nutrient supply. The genes H3, 18S and cytochrome c oxidase subunit 1 were highly conserved, revealing near-absence of local variation within Stylops. Ovaries of hosts with male Stylops contained poorly developed eggs while those of hosts with female Stylops were devoid of visible eggs, which might be due to a higher protein demand of female Stylops. Male Stylops, which might have a more energy-consuming development, led to a reduction in head width of their hosts. Host masculinization was present in the leaner shape of the metabasitarsus of stylopized females and is interpreted as a by-product of manipulation of the host's endocrine system to shift its emergence. Stylopization intensified tergal hairiness, most strongly in hosts with female Stylops, near the point of parasite extrusion, hinting towards substance-induced host manipulation.
In order to enhance genetic potential of chickpea materials from the National University of Córdoba Breeding Programme and Germplasm collection (Argentina), a study for a comprehensive understanding of the amount and pattern of genetic variation within and between genotypes was carried out by applying a multivariate analysis form single simple repeats (SSR) and morphological data. Molecular data were also used to determine the discriminating power for genotype identification, and to find the optimal primer combination to ensure unambiguous identification. With the analysis of 15 SSR markers on 53 genotypes, a total of 58 alleles were detected with individual values ranging from one to nine alleles per locus. High values of discriminating power (Dj ⩾ 0.7, PIC ⩾ 0.7), and low values of confusion probability (Cj ⩽ 0.23) were obtained for at least four evaluated markers. The combination of TA113 + TA114 + H1B09 + TA106 primers was effective for discriminating the 53 chickpea genotypes with a cumulative confusion probability value (Ck) of 9.60 × 10−4. Except for some exceptions, individual chickpea genotypes within a cluster in the consensus tree were definitely more closely related with each other by the origin or pedigree. The results confirmed that both multivariate data analysis methods, ordination and clustering, were complementary. In most genotypes, discriminant principal component analysis classification was consistent with the original clusters defined by molecular data. Differences in results from molecular and morphological data indicate that they provide complementary and relevant information for establishing genetic relationships among chickpea materials and a better description and interpretation of the available variability in the germplasm collection.
Astronium concinnum Schott ex Spreng. (Anacardiaceae) is a species used in civil construction, naval, luxury furniture, in addition to the potential for recovery and restoration of habitats. The objective of this work was to characterize the diversity and genetic structure of the A. concinnum in the Conservation Units, National Forest of Pacotuba and Private Natural Heritage Reserve of Cafundó, located in the south of the state of Espírito Santo. Eight ISSR primers were used, which produced 121 DNA fragments and 73.55% polymorphism. In the analysis of genetic dissimilarity, seven distinct groups were identified, with the majority of individuals (from both Conservation Units) being brought together into a single group. The genetic diversity of Nei (H*) and the Shannon index (I*), provided values for the species of 0.312 and 0.473, respectively, indicating the genetic diversity conserved in the species and its potential use for collecting genetically diversified seeds. The analysis of molecular variance revealed that most of the diversity (92.54%) is distributed within populations and the value of gene flow (Nm = 10.629) indicates the high rate of genetic exchange between Conservation Units. The results of the genetic structuring indicated the division of individuals into three genetic groups (K = 3), however, it was possible to observe a mixture of genetic material with the sharing of alleles between the three groups. The results indicate that A. concinnum trees maintain genetic diversity for their maintenance. In addition, the potential of the analysed individuals was certified as future matrixes for seed collection.
Beachpea (Vigna marina) is a halophytic wild leguminous plant which occurs throughout tropical and subtropical beaches of world. As quantitative trait loci (QTLs) for salt tolerance in V. marina and its crossability with other Vigna species are known, the current study was undertaken to know the presence of these QTLs in the V. marina accessions along with check varieties of pulses. Accordingly, 20 Vigna genotypes (15 accessions of V. marina collected from sea-shore areas of Andaman and Nicobar Islands along with five check varieties of green gram and black gram) were subjected to molecular characterization using seven simple sequence repeat (SSR) markers associated with salt tolerance. Of the markers used, only four SSR markers amplified in the studied germplasm. Number of alleles detected per primer and size of alleles ranged from 1 to 3 and 100 to 325 bp, respectively. Polymorphism information content and heterozygosity values ranged from 0.305 to 0.537 and 0.375 to 0.612, respectively. Three major clusters, cluster I, II and III were obtained at Jaccard's similarity coefficient value of 0.48 through the un-weighted paired group method with arithmetic means method of cluster analysis. It grouped green gram and black gram genotypes in clusters I (04) and II (01), whereas all V. marina genotypes were grouped in cluster III (15). Principal co-ordinate analysis explained 85.9% of genetic variation among genotypes which was further confirmed by cluster analysis. This study indicated the effectiveness of SSR markers in separating cultivated Vigna species from wild V. marina. The findings will be useful for transferring trait of robust salt tolerance of V. marina in cultivated Vigna species using marker-assisted breeding.
The production of specialty coffee has several factors and parameters that are added up in the course of production, so that the quality is expressed in the act of consumption. Based on this scenario, this study included the analysis of ten genotypes of arabica coffee, the materials being subjected to irrigated and rainfed water regimes, in a low altitude region, to identify responses for sensory and physical–chemical quality. The genotypes were evaluated in a split-plot scheme with a randomized block design, with three replications. Arabica coffee fruits were harvested with 80% cherry seeds and processed by the wet method. Subsequently, the characteristics related to physical–chemical and sensory analyses were evaluated. The genotypes of the Paraíso group showed great variability for the physical–chemical and sensory variables for rainfed and irrigated regimes. The genotypes of the Catuaí group, however, showed less variability for sensory characteristics in both cultivation environments and for physical–chemical characteristics in the irrigated regime. In the sensorial data set, the genotypes Catuaí 144 CCF and Catuaí 144 SFC (when irrigated) and Paraíso H 419-3-3-7-16-2, Paraíso H 419-3-3-7-16-11 and Catucaí 24-137 (rainfed cultivation), are more favourable to the production of specialty coffee at low altitude.
Conservation of animal genetic resources requires regular monitoring and interventions to maintain population size and manage genetic variability. This study uses genealogical information to evaluate the impact of conservation measures in Europe, using (i) data from the Domestic Animal Diversity Information System (DAD-IS) and (ii) a posteriori assessment of the impact of various conservation measures on the genetic variability of 17 at-risk breeds with a wide range of interventions. Analysis of data from DAD-IS showed that 68% of national breed populations reported to receive financial support showed increasing demographic trends, v. 51% for those that did not. The majority of the 17 at-risk breeds have increased their numbers of registered animals over the last 20 years, but the changes in genetic variability per breed have not always matched the trend in population size. These differences in trends observed in the different metrics might be explained by the tensions between interventions to maintain genetic variability, and development initiatives which lead to intensification of selection.
Conservation of animal genetic resources is considered as one of the main challenges of today's breeding. Every breed of livestock is a valuable element of the world's animal genetic diversity. Over the last few decades, considerable reductions in the number of local breeds and their sizes have been registered. This trend caused the need to implement conservation programmes for endangered goose species. Poland has a number of local goose breeds which are the achievements of many generations of breeders. The objective of this review was to present the current status of the realised conservation programmes for 14 goose breeds in Poland by analysing population and molecular parameters. The conservation status of these populations has been presented including the effective population sizes, hypothetical inbreeding level, trends in performance traits as well as parameters estimated on the basis of genetic markers. In all the cases population sizes were well over 100 individuals, which is the minimum recommended by the FAO for conservation flocks. The effective population size ranged from 179 to 452, affecting a relatively low inbreeding level from 0.1 to 0.74%. The estimated correlations between hypothetical inbreeding rates and reproduction traits were negative. The heterozygosity coefficients varied from 0.27 (Biłgorajska breed) to 0.55 (Garbonosa breed). Generally, the parameters for goose breeds in Poland were compatible with the recommendations of the FAO.
Decreased reliance on pesticides can be achieved through a clever use of eco-evolutionary knowledge via intercropping economically valuable crops with companion plants that can hamper pest outbreaks. We created a greenhouse multi-layered microcosm system to test two potato peach aphid clones, performing alone or in competition, on mixes of genetically variable cultivars of cabbage, with and without onion. The onion acted as a nuisance/disturbance for the pest, which was generally for the benefit of the cabbage albeit both plants sharing space and nutrients. The onion effect was context-specific and differed by aphid genotype. Onion variable nuisance negatively affected the numbers of one aphid genotype (green) across all contexts, while the other genotype (pink) numbers were decreased in two contexts only. However, the green performed better than the pink on all cases of cabbage di-mixes despite its numbers being capped when the onion was present. Further, there was also a general aphid propensity to wander off the plant along with a differential production of winged morphs to escape the onion-affected environments. Moreover, through a comparative increase in dry mass, which was subject to onion and aphid effects, a diversity effect was found where the cabbages of fully genetically variable microcosms sustained similar final dry mass compared with non-infested microcosms. Our findings provide fresh insights into the use of multi-layered contextual designs that not only allow disentangling the relative effects of genetic variation and modes of interaction, but also help integrate their benefits into pest management in view of companion planting.
The aim of this study was to estimate genetic parameters for environmental sensitivities in milk yield and composition of Iranian Holstein cows using the double hierarchical generalized linear model (DHGLM) method. Data set included test-day productive records of cows which were provided by the Animal Breeding Center and Promotion of Animal Products of Iran during 1983 to 2014. In the DHGLM method, a random regression model was fitted which included two parts of mean and residual variance. A random regression model (mean model) and a residual variance model were used to study the genetic variation of micro-environmental sensitivities. In order to consider macro-environmental sensitivities, DHGLM was extended using a reaction norm model, and a sire model was applied. Based on the mean model, additive genetic variances for the mean were 38.25 for milk yield, 0.23 for fat yield and 0.03 for protein yield in the first lactation, respectively. Based on the residual variance model, additive genetic variances for residual variance were 0.039 for milk yield, 0.030 for fat yield and 0.020 for protein yield in the first lactation, respectively. Estimates of genetic correlation between milk yield and macro- and micro-environmental sensitivities were 0.660 and 0.597 in the first lactation, respectively. The results of this study indicated that macro- and micro-environmental sensitivities were present for milk production traits of Iranian Holsteins. High genetic coefficient of variation for micro-environmental sensitivities indicated the possibility of reducing environmental variation and increase in uniformity via selection.
Breast cancer (BC) is one of the most complex, diverse and leading cause of death in women worldwide. The present investigation aims to explore genes panel associated with BC in different African regions, and compare them to those studied worldwide.
We extracted relevant information from 43 studies performed in Africa using the following criteria: case-control study, association between genetic variations and BC risk. Data were provided on mutations and polymorphisms associated with BC without fixing a specific date. Case-only studies and clinical trials were excluded.
Our study revealed that the majority of African BC genetic studies remain restricted to the investigation of BRCA1 and BRCA2 genes and differences in their mutations spectrum. Therefore, it is necessary to encourage African researchers to characterize more genes involved in BC using methods generating global information such as next-generation sequencing in order to guide specific and more effective therapeutic strategies for the African community.
Cystic echinococcosis (CE) is a severe parasitic disease caused by the species complex Echinococcus granulosus sensu lato. Human infections are most commonly associated with E. granulosus sensu stricto (s.s.), comprising genotypes G1 and G3. The objective of the current study was to provide first insight into the genetic diversity and phylogeography of genotype G3. Despite the epidemiological importance of the genotype, it has remained poorly explored due to the ambiguity in the definition of the genotype. However, it was recently demonstrated that long sequences of mitochondrial DNA (mtDNA) provide a reliable method to discriminate G1 and G3 from each other. Therefore, we sequenced near-complete mtDNA of 39 G3 samples, covering most of the known distribution range and host spectra of the genotype. The phylogenetic network revealed high genetic variation within E. granulosus s.s. G3 and while G3 is significantly less prevalent worldwide than G1, the genetic diversity of both of the genotypes is equally high. We also present the results of the Bayesian phylogeographic analysis, which yielded several well-supported diffusion routes of genotype G3 originating from Turkey and Iran, suggesting the Middle East as the origin of the genotype.