Genetic and Phenotypic Variation of Campylobacter jejuni NCTC11168 Caused by flhA Mutation during Laboratory Passage

Objective Campylobacter jejuni NCTC11168 is commonly used as a standard strain for flagellar biosynthesis research.In this report,two distinguished phenotypic isolates(CJ1Z,flhA mutant strain,lawn;CJ2S,flhA complemented strain,normal colony)appeared during laboratory passages for NCTC11168.Methods Phenotypic assessments,including motility plates,transmission electron microscopy,biofilm formation assay,autoagglutination assay,and genome re-sequencing for these two isolates(CJ1Z,flhA mutant strain;CJ2S,flhA complemented strain)were carried out in this study.Results Transmission electron microscopy revealed that the flagellum was lost in CJ1Z.Phenotypic assessments and genome sequencing of the two isolates were performed in this study.The capacity for biofilm formation,colony auto-agglutination,and isolate motility was reduced in the mutant CJ1Z.Comparative genomic analysis indicated a unique native nucleotide insertion in flhA(nt,2154)that caused the I719Y and I720Y mutations and early truncation in flhA.Conclusion FlhA has been found to influence the expression of flagella in C.jejuni.To the best of our knowledge,this is the first study to describe the function of the C-terminal of this protein.

Leaf phenotypic variation of endangered plant Tetracentron sinense Oliv.and influence of geographical and climatic factors

To analyze the degree and pattern of phenotypic variation in leaves of Tetracentron sinense Oliv from the perspective of genetic and environmental adaptation and thus contribute to effective evidence-based conservation and management strategies for germplasm resources,we measured 17 morphological and epidermal micromorphological leaf traits from 24 natural populations of T.sinense.Nested analysis of variance,multiple comparison,principal component analysis(PCA),cluster analysis,and correlation analysis were used to explore phenotypic leaf variation among and within populations and potential correlations with geographic and environmental factors.There were significant differences in 17 leaf phenotypic traits among and within populations.The mean phenotypic differentiation coefficient of the 17 traits was 56.34%,and the variation among populations(36.4%)was greater than that within populations(27.2%).The coefficient of variation(CV)of each trait ranged from 4.6 to 23.8%,and the mean was 11.8%.Phenotypic variation of leaves was related to environmental factors such as average annual sunshine hours,average July temperature,and average annual rainfall.The variation changed along gradients of longitude,latitude,and altitude.The PCA clustered the 24 natural populations into four groups.Our study suggests that phenotypic variation in T.sinense occurred primarily among populations,with moderate levels of phenotypic differentiation among populations and low levels of phenotypic variation within populations.The plant’s poor adaptability to the environment is likely an important contributor to its endangerment.Accordingly,conservation strategies are proposed to protect and manage the natural populations of T.sinense.

Phenotypic Variation among and within Three Peppers Species(Capsicum)from Mexico

The phenotypic variation and its distribution among species,morphotypes,and among and within populations was estimated in 71 populations pertaining to 15 morphotypes of three domesticated species of Capsicum from Mexico.Collections were made in the states of Sinaloa,Nayarit,Oaxaca,Tabasco,and Yucatán in two agroecosystems:Backyard-garden and monoculture.Fifteen phenotypic characteristics were analyzed through one-way variance analysis and multivariate analyses of principal components analysis(PCA)and hierarchical clustering using Ward’s method.The study was performed in a uniform greenhouse experiment.A high variation was found among and within populations in all the measured characteristics.Of the total variation,13.0%was distributed among species,27.9%among morphotypes,8.1%among populations,and 51.0%within populations.Because plants grew in a uniform environment,these results indicate that the differences observed among and within species,morphotypes,and populations have a genetic basis.Univariate and multivariate analyses clearly differentiated morphotypes,suggesting that the category of morphotypes must be used to nominate the infraspecific variation in the domesticated Capsicum.The principal components analysis identified a total of 15 principal components that contributed to explain the total variation.The first two components explained 59.64%of the total variation and seven components explained more than 90%of the total variation.Among the measured characteristics,number of seed per fruit,weight of the fruit,width of the fruit,length of the fruit,stem diameter,days to flowering,and height of the plant contributed to component 1 variation,whereas width of the leaf,length of the leaf,and number of locules,number of fruits and number of seeds per plant contributed to component 2.The hierarchical clustering separated the populations and the morphotypes in two large different groups.One group consisted of populations collected in monoculture conditions and the other group corresponded to population collected from backyard-garden conditions.The monoculture populations were characterized mainly by their longer,wider,and higher weight fruits,plants were of less height,had smaller stem diameters,and lower number of fruits than the populations collected from the backyard-garden conditions.The backyard-garden populations of the Capsicum annuum and Capsicum frutescens species,considered wild or semi-domesticated,constituted a non-differentiated phenotypic group that does not allow dividing them in different species.

Is intraspecific trait differentiation in Parthenium hysterophorus a consequence of hereditary factors and/or phenotypic plasticity?

Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,we studied the persistence of substantial morpho-functional variations within the individuals of alien invasive plant,Parthenium hysterophorus in Chandigarh,India,through field surveys.Based on observed differences,the individuals were categorized into two morphotypes,PAand PB.PAhad higher leaf area,leaf biomass,and chlorophyll content as compared with PB.However,PBhad a higher stem circumference,stem specific density,twig dry matter content,profuse branching,bigger canopy,and better reproductive output than PA.To substantiate the persistence of intraspecific variations in P. hysterophorus and to deduce the possible genesis of these variations,we propagated both the morphotypes under experimental conditions in winter and summer.Apart from the key morpho-functional differences observed during the field studies,protein and carbohydrate metabolism were studied in leaves and roots of the propagated plants.Differences in plant metabolism were observed only during the early growth period,whereas the morpho-functional traits varied in the mature flowering plants.The effect of growth season was highly significant on all the studied morpho-functional and biochemical parameters(p ≤0.05).Parent morphotypes(P) and interactions between morphotypes and seasons significantly affected several growth parameters(p ≤0.05).The analyses revealed that the contrasting growth conditions at the time of transplantation and early growth may regulate the phenotype of P. hysterophorus.The pattern of intraspecific variations observed during the study is justified to consider morphotype PAas winter biotype and morphotype PBas summer biotype of P. hysterophorus.The study points towards the role of plasticity or a combination of genetic and environmental(G×E) factors in producing the phenotypic variability observed in the population of P. hysterophorus.

Deciphering the modifiers for phenotypic variability of X-linked adrenoleukodystrophy

X-linked adrenoleukodystrophy(X-ALD),an inborn error of peroxisomalβ-oxidation,is caused by defects in the ATP Binding Cassette Subfamily D Member 1(ABCD1)gene.X-ALD patients may be asymptomatic or present with several clinical phenotypes varying from severe to mild,severe cerebral adrenoleukodystrophy to mild adrenomyeloneuropathy(AMN).Although most female heterozygotes present with AMN-like symptoms after 60 years of age,occasional cases of females with the cerebral form have been reported.Phenotypic variability has been described within the same kindreds and even among monozygotic twins.There is no association between the nature of ABCD1 mutation and the clinical phenotypes,and the molecular basis of phenotypic variability in X-ALD is yet to be resolved.Various genetic,epigenetic,and environmental influences are speculated to modify the disease onset and severity.In this review,we summarize the observations made in various studies investigating the potential modifying factors regulating the clinical manifestation of X-ALD,which could help understand the pathogenesis of the disease and develop suitable therapeutic strategies.

Estimation of Variability, Heritability and Genetic Advance for Phenological, Physiological and Yield Contributing Attributes in Wheat Genotypes under Heat Stress Condition

The investigation was carried out in focusing the genetic variability for different traits of wheat influenced by heat tolerance mechanism to find out relationships among phenological, physiological and yield contributing traits. Spring wheat cultivar of 25 genotypes were selected and cultivated under late sowing condition at the Regional Wheat Research Institute, Shympur, Rajshahi, Bangladesh from December, 2016 to April, 2017. Significant variability among the genotypes exposed for different traits related to heat tolerance. Results showed that the genotypes G24, G10, G01, G13, G16, G25 and G14 ranked as better category considering maximum number of traits in mean performance indicating their tolerance to heat stress under late sowing condition. Phenotypic variances (σg2) of all traits were greater than those of genotypic variances (σg2). The same trends were also found in their co-efficient of variances. The phenotypic co-efficient of variances (PCV) of all traits were greater compare to those of genotypic co-efficient of variances (GCV) and their values were closer to each other. The heading days (HD), canopy temperature at vegetative stage (CTvg), canopy temperature at grain filling stage (CTgf), biomass, plant height (PH), spike/m2 (SPM), spikelet/spike (SPS), grain/ spike (GPS), thousand grain weight (TGW) and yield exhibited higher heritability (hb2) estimated under irrigated late sowing (ILS) condition. Under the same ILS condition SPAD, SPM, SPS, GPS, TGW and yield showed moderate to high genetic advance (GA) obtained through computing their mean percentage (%) and the rest traits HD, maturity days (MD), CTvg, CTgf, biomass, PH and harvest index (HI) exposed smaller genetic advance (% mean). The co-efficient of variation (CV%) of all attributes in all genotypes were significantly lower (1.36 - 6.96). Both heritability and genetic advance were found lower for MD, SPAD and HI indicated their non additive genetic effects for which these traits might not be recommended for selection. However, spike/m2, spikelet/spike, grain/spike, thousand grain weight and yield belonged to higher heritability and high to moderate genetic advance in mean percentage (%) along with wide genetic variation and lower environmental influence in heat stress situation indicated the most likely heritability due to the effects of additive genes that might be suggested as effective process of selection for these traits in heat stress condition.

Plasticity of leaf morphology of Bruguiera sexangula to salinity zones in Bangladesh's Sundarbans

Bruguiera sexangula(Lour.)Poir is an exclusive evergreen mangrove species to the Sundarbans of Bangladesh.It grows well in moderate saline zones with full sunlight.This study presents leaf morphological plasticity in B.sexangula to saline zones.Leaves were sampled from different saline zones and various morphological traits were measured.The results exposed a wide deviations of leaf size parameters:leaf length varied 6.6–17.3 cm;width 2.7–7.8 cm;upper quarter width 2.2–6.5 cm;down quarter width 2.5–7.3 cm;and petiole length 0.17–1.43 cm.Leaf length was significantly larger in fresh water than in other salinity zones,whereas,leaf width,upper and lower leaf quarters were significantly larger in medium saline zone.Leaf shape parameters showed a large variation among saline zones.Leaf base angle was significantly larger in both medium and strong salinity zones.Tip angle was significantly greater in medium salinity zone.Leaf perimeter was significantly larger in fresh water but leaf area was significantly bigger in medium saline zone.Leaf index and specific leaf area were maximum in moderate saline zone.Plasticity index was the highest in moderate saline for almost all the parameters presented.The ordination(PCA)showed clusters of leaf samples although there were some overlap among them which suggested a salt-stress relationship among salinity zones.The results indicate that B.sexangula had a plasticity strategy on leaf morphological parameters to salinity in the Sundarbans.This study will provide basic information of leaf plasticity of this species among saline zones which will help for site selection of coastal planting and will also provide information for policy makers to take necessary steps for its conservation.

Description of Flower Biology of Under-Exploited Species, <i>Zingiber barbatum</i>(Wall.) from Myanmar

Characterization of the reproductive morphology in genus Zingiber is still relevant on classical taxonomic studies because most of the species are phenotypically similar and difficult to distinguish in the absence of the flowering stage. Reports mainly derived based on the herbarium collections are insufficient for the detailed morphological review. Zingiber barbatum (Wall.) belongs to the genus Zingiber and has been neglected for a long time. Existed intraspecific morphological and genetic variations also intricate the description of this species. The objective of this study was to characterize the reproductive morphology of under-exploited Z. barbatum species. The study was done based on the traditional description of morphology and habit of inflorescence and flowers, with a recording of minimum quantitative and qualitative parameters and phenological observation regarding inflorescence life span and duration of blossom. Assessment of reproductive morphology displayed phenotypic variations regarding inflorescences habit during the growth stage and morphological features of the flower. Perhaps, an existed variation was driven by eco-geographical factors resulting in reproductive isolation due to which genetic divergence might occur. The taxonomic affiliation of Z. barbatum based on inflorescence habit has been confirmed. This is the first comprehensive report regarding flower biology on Z. barbatum.

A Study on Genetic Variability, Character Association and Path Co-Efficient Analysis on Morphological and Yield Attributing Characters of Taro [Colocasia esculenta (L.) Schott]

The study investigated genotypic and phenotypic co-efficients of variation, heritability, genetic advance at 5% selection intensity and in percentage of population mean of nine characters (plant height, leaf number, length and width of leaf lamina, number and weight of cormels per plant, weight of corm per plant, dry matter percentage in the tubers and tuber yield per from 14 cultivars of taro [Colocasia esculenta (L.) Schott]). Results indicated highest genotypic co-efficient of variation for dry matter percentage (47.91), which was 95.78% of the phenotypic co-efficient of variation, whereas tuber yield per plant showed the widest range (819.37). Number of cormels per plant and dry matter percentage ehibited considerably higher heritability (84.90% and 91.70%, respectively) and genetic advance (81.19 and 79.00, respectively), indicating the potentiality of selection for improvement of such characters. These two characters were found to be positively correlated to tuber yield per plant. Path analysis revealed that weight of cormels per plant possessed the highest direct effect on tuber yield, indicating the importance of selection based on this character to increase tuber yield per plant.

Phenotypic variations of wheat cultivars from the North China Plain in response to cadmium stress and associated single nucleotide polymorphisms identified by a genome-wide association study

Understanding the genetic mechanisms for cadmium (Cd) uptake and translocation in common wheat (Triticum aestivum) is of significance in food Cd contamination control. In this study, a diverse panel of 132 wheat cultivars was collected from the North China Plain. The cultivars were evaluated in terms of their phenotypic variations in response to Cd stress and subjected to a genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with the phenotypic variations at the seedling stage. Significant phenotypic variations with high heritability were observed among the wheat cultivars exposed to 40 μmol L-1 Cd for the studied traits, including root length (RL), shoot length (SL), root and shoot dry biomasses (RDW and SDW, respectively), root and shoot Cd concentrations (RCD and SCD, respectively), and Cd translocation factor (TF). Mean RCD, SCD, and TF ranged from 1.0 to 33.8, 0.125 to 2.022, and 0.009 to 0.321 mg g-1, respectively. Cluster analysis showed that wheat cultivars with higher RL, SL, RDW, and SDW under Cd stress were able to accumulate more Cd in root, leading to a lower Cd TF. Mixed linear model-based association analysis detected 17 novel significant marker-trait associations (MTAs), four of which were significant at a genome-wide scale. Most of the significant MTAs controlled Cd TF and explained 17.17%–26.47% of the phenotypic variations. Some of the SNP loci were physically close to a reported Cd-related quantitative trait locus or gene on wheat chromosomes. Results of this study provided a list of wheat cultivars with the potential of low Cd accumulation and enriched our knowledge on the genetic basis of Cd uptake and translocation in wheat. Pyramiding breeding of superior alleles detected in this study may additionally reduce Cd accumulation of improved wheat cultivars with excellent agronomic traits.

Ecogeographical variation of 12 morphological traits within Pinus tabulaeformis: the effects of environmental factors and demographic histories

Aims More data are needed about how genetic variation(GV)and envi-ronmental factors influence phenotypic variation within the natural populations of long-lived species with broad geographic distribu-tions.To fill this gap,we examined the correlations among envi-ronmental factors and phenotypic variation within and among 13 natural populations of Pinus tabulaeformis consisting of four demo-graphically distinct groups within the entire distributional range.Methods Using the Akaike’s information Criterion(AiC)model,we measured 12 morphological traits and constructed alternative candidate models for the relationships between each morphological trait and key climatic variables and genetic groups.We then compared the AiC weight for each candidate model to identify the best approximating model for ecogeographical variation of P.tabulaeformis.The partitioning of vari-ance was assessed subsequently by evaluating the independent vari-ables of the selected best models using partial redundancy analysis.Important Findings Significant phenotypic variation of the morphological traits was observed both within individual populations and among populations.Variation partition analyses showed that most of the phenotypic variation was co-determined by both GV and climatic factors.GV accounted for the largest proportion of reproductive trait variation,whereas local key climatic factors(i.e.actual evapotranspiration,AET)accounted for the largest proportion of phenotypic variation in the remaining investigated traits.Our results indicate that both genetic divergence and key environmental factors affect the phenotypic variation observed among populations of this species,and that reproductive and vegetative traits adaptively respond differently with respect to local environmental conditions.This partitioning of factors can inform those making predictions about phenotypic variation in response to future changes in climatic conditions(particularly those affecting AET).

From micro-to macroevolution:brood parasitism as a driver of phenotypic diversity in birds

A fun dame ntal question in biology is how diversity evolves and why some clades are more diverse than others.Phenotypic diversity has often been shown to result from morphological adaptation to different habitats.The role of behavioral interactions as a driver of broadscale phenotypic diversity has received comparatively less attention.Behavioral interactions,however,are a key agent of natural selection.Antagonistic behavioral interactions with predators or with parasites can have significant fitness consequences,and hence act as strong evolutionary forces on the phe no type of species,ultimately gen erating diversity betwee n species of both victims and exploiters.Avian obligate brood parasites lay their eggs in the nests of other species,their hosts,and this behavioral interaction between hosts and parasites is often considered one of the best examples of coevolution in the natural world.In this review,we use the coevolution between brood parasites and their hosts to illustrate the potential of behavioral interactions to drive evolution of phenotypic diversity at different taxonomic scales.We provide a bridge between behavioral ecology and macroevolution by describing how this interaction has increased avian phenotypic diversity not only in the brood parasitic clades but also in their hosts.

Experimental evaluation of reproductive response to climate warming in an oviparous skink

The impact of climate warming on organisms is increasingly being recognized.The experimental evaluation of phenotypically plastic responses to warming is a critical step in understanding the biological effects and adaptive capacity of organisms to future climate warming.Oviparous Scincella modesta live in deeply-shaded habitats and they require low optimal temperatures during embryonic development,which makes them suitable subjects for testing the effects of warming on reproduction.We raised adult females and incubated their eggs under different thermal conditions that mimicked potential climate warming.Female reproduction,embryonic development and hatchling traits were monitored to evaluate the reproductive response to warming.Experimental warming induced females to lay eggs earlier,but it did not affect the developmental stage of embryos at oviposition or the reproductive output.The high temperatures experienced by gravid females during warming treatments reduced the incubation period and increased embryonic mortality.The locomotor performance of hatchlings was not affected by the maternal thermal environment,but it was affected by the warming treatment during embryonic development.Our results suggest that climate warming might have a profound effect on fitness-relevant traits both at embryonic and post-embryonic stages in oviparous lizards.