In opposition to what has been reported to date for Siphonaria species , we found genetic differen- tiation among individuals sampled from the different shore heights. However, genetic substructuring has been observed for mollusks with different morphotypes inhabiting different shore heights [51, 52]. For exam- ple, the marine gastropod Littorina fabalis has a small and a large morph in microhabitats with different wave exposure, but their distribution overlaps where wave exposure is intermediate. These morphotypes differed genetically . Similarly, Littorina picta (currently Echinolittorina hawaiensis) and Littorina saxatilis show different shell morphs, representing ecotypes adapted to distinct ecological conditions such as different wave exposure and presence of predators, also with substan- tial geneticdifferentiation linked to morphs . The limpet Nacella concinna has two morphotypes in Argen- tina, one inhabiting the intertidal (during summer) and the other inhabiting the subtidal (during fall and winter). The genetic differences detected using ISSRs indicate that the two forms can be considered as genetically distinct Fig. 3 Plot showing Logistic relation of proportion of mortality of Siphonaria lessonii related to shore heights at different periods of exposure (12 h, 24 h and 48 h). The line corresponds to adjusted logistic function. Different lines types indicate different shore heights
Environmental temperature has profound effects on the biological performance and biogeographical distribution of ectothermic species. Variation of this abiotic factor across geographic gradients is expected to produce physiologicaldifferentiation and local adaptation of natural populations depending on their thermal tolerances and physiological sensitivities. Here, we studied geographic variation in whole-organism thermal physiology of seven populations of the porcelain crab Petrolisthes violaceus across a latitudinal gradient of 3000 km, characterized by a cline of thermal conditions. Our study found that populations of P. violaceus show no differences in the limits of their thermal performance curves and demonstrate a negative correlation of their optimal temperatures with latitude. Additionally, our findings show that high-latitude populations of P. violaceus exhibit broader thermal tolerances, which is consistent with the climatic variability hypothesis. Interestingly, under a future scenario of warming oceans, the thermal safety margins of P. violaceus indicate that lower latitude populations can physiologically tolerate the ocean-warming scenarios projected by the IPCC for the end of the twenty-first century.
Intertidal animals frequently encounter extreme thermal stress during aerial emersion (Helmuth and Hofmann, 2001; Gilman et al., 2006; Helmuth et al., 2006a; Miller et al., 2009), and temperature is regarded as one of the most important factors determining their zonation patterns (Wolcott, 1973; Hochachka and Somero 2002; Davenport and Davenport, 2005). Three decades of high-resolution data show that 71% of the world’s coastlines are significantly warming, and extremely hot days are becoming more common in 38% of coastal areas (Lima and Wethey, 2012). Moreover, the mosaic patterns of thermal stress on rocky shores along a latitudinal gradient make some shores more thermally stressful than expected based strictly on latitude, such that local populations are more vulnerable to climate change (Helmuth et al., 2002; Helmuth et al., 2006b). Consequently, significant changes in intertidal communities have been recorded, based on long-term in situ observations, during the past several decades (Barry et al., 1995; Southward et al., 1995). Physiological adaptation is one of the main response options for organisms facing global change (Hofmann and Todgham, 2010), and the potential for acclimatization and genetic adaptation will determine ‘winners’ and ‘losers’ in the future (Hochachka and
Microsatellites, also known as SSR (Simple Sequence Repeat), have been indicated, among different molecular marker classes, for genetic variability studies, allelic frequency calculations, deviations from Hardy-Weinberg equilibrium, genome genetic and physical mapping, genotype identification and discrimination, paternity tests, as well as for population-genetics studies, since they are of a codominant nature and because they are one of the most polymorphic molecular marker classes currently available (Ferreira and Grattapaglia, 1998).
The gradient of environmental variation seen along the marine nearshore is well known to strongly influence species distribution (Doty, 1946; Stillman and Somero, 1996), and some physiological and biochemical correlates with environmental variation and species distribution have been examined. Organisms that live high in the intertidal zone must be able to withstand large variation in environmental condition, whereas those living lower in the intertidal zone or subtidally experience much less environmental variation and therefore do not necessarily require the capacity to survive harsh conditions. Of all the environmental variables that are known to fluctuate in the intertidal zone, temperature, and the role it plays in species distribution, has been the most studied. In particular, the vertical zonation patterns of porcelain crabs (genus Petrolisthes) along the nearshore has been shown to be positively associated with upper thermal tolerance limits, with the most warm- temperature-tolerant crabs being located higher in the intertidal zone, where water temperatures can be much higher than lower in the intertidal zone (Stillman and Somero, 2000). Stillman and Somero further demonstrated through the application of phylogenetically independent contrasts that the upper thermal tolerance limits of individual species evolved in response to maximal microhabitat temperatures (Stillman and Somero, 2000). Few studies have used the marine nearshore environment to understand adaptation to other environmental variables.
compiled data on forest cover between 1773 and 1935 from  and in 1997 from . The habitat maps were then digitised in ARC GIS 10.1 (ESRI, Redlands, CA, USA). Only the 1997 map was accurately georeferenced as the others were originally hand drawn in the 1940s from historical records of logging and cane production (Figure 1). We then tested whether genetic diversity was related to the time for which subpopulations had been isolated using Pearson’s coefficient of correlation in R 2.15.3. We assumed that the loss of native habitats prevented natural migration and eventually reduced genetic diversity. P. guimbeaui is a habitat specialist and is mostly reliant on native habitats that have high tree diversity and tall, large trees with cavities (Buckland et al., submitted). The maximum dispersal distance of 28 adult P. guimbeaui monitored for a year was ,15 m (S. Buckland, unpublished data). There are no data on dispersal in sub-adult and juvenile P. guimbeaui, but the maximum recorded dispersal distance for P. ornata (ornate day gecko), a similar-sized Mauritian species, was 87 m . While P. guimbeaui also persists in the presence of four exotic tree species, i.e. Eucalyptus tereticornis (eucalyptus), Haematoxylum campechianum (campeche), Mangifera indica (mango) and Terminalia arjuna (terminalia), these trees are usually scattered and probably act as ecological traps; there are no data on the density of P. guimbeaui in these exotic plantations, and it has never been recorded on buildings or in agricultural land. Figure 1. Pattern of deforestation in Mauritius from 1773 to 1997. The red dots indicate the 10 subpopulations for which both microsatellite and mtDNA analyses were conducted, and the yellow dots the three subpopulations for which only mtDNA analyses were carried out. The blue stars mark subpopulations not sampled and the black region within the purple dotted line on the 1997 map shows the Black River mountains. All subpopulation locations were transposed by 1 km.
Despite this extensive literature, most of the knowledge comes from the study of HA populations, thus it remains unclear whether the same traits have developed under moderate hypoxia. Therefore, our focus on the Calchaqu ıes allows us to investigate for the first time phenotypic and genetic adaptations in an Andean population at IA, although this is not without challenges. For a start, Calc- haqu ıes are thought to be closely related to other HA pop- ulations (Frank 2008), yet their demographic history is poorly researched. The Calchaqu ıes belong to the Diaguita group of small tribes scattered predominantly in the valleys of Northwest Argentina (1680–3015 m) (De Hoyos 2009). Archeological evidence around the Calchaqu ı valleys sug- gest that settlement dates back to 7200 (Rodr ıguez et al. 2003) and 6500 years ago (Somonte and Baied 2013). Moreover, the region was a migration corridor during the Inca expansion in the XV century; yet, the extent of gene flow that took place at that time is largely unknown. This dearth of population history can potentially complicate the disentangling of demographic and adaptive signals.
the most important food crops of the world which provide bulk of raw materials for the livestock and human consumption and many agro-allied industries in the world. It is drought tolerant which allows farmers to use less water for its cultivation than similar crops. Sorghum is indigenous to Africa, and was also grown in India before recorded history and in Assyria as early as 700 BC. It can be classified into two types: Forage types (mainly for forage or animal feed) and grain types (mainly for human consumption). Fodder yield is a complex character which is dependent on many other component characters. Knowledge on type of association between yield and its components themselves greatly help in evaluating the contribution of different components towards yield and is essential for the formulation of breeding programmes. The information on the nature of association between yield and its components help in simultaneous selection for many characters associated with yield improvements. The estimates of correlation coefficients among different characters indicate the extent and direction of association. The correlation co-efficient provide a reliable measure of association among the characters. To improve the quality of fodder to be supplied to the cattle, it is imperative to know the association of different quality traits with the morphological and physiological traits of forage sorghum. It is also very important to know the association of HCN content, which is an anti quality trait in forage sorghum, with the morpho-
priority in Burkina Faso. Hence the interest of this study, which aims to evaluate the genetic diversity of a collection of H. cannabinus from seven provinces of Burkina Faso using SSRs microsatellite markers. More specifically, it aims to determine the level of genetic diversity of H. cannabinus from Burkina Faso; to evaluate the distribution of allelic frequencies between geographical regions and to define the potential genetic groups of cultivated H. cannabinus.
Furthermore, UPGMA tree clustering was gener- ated using Ds data (Figure 4). Bootstrap values are based on 1 000 replicates, and their support to the main clusters is as high as 62.5% and 100% (Figure 4). A similar phylogenetic tree structure was also ob- tained with the neighbour-joining algorithm (Figure 5). This neighbour-joining method assumes that two neighbours (the two nearest taxa on an unrooted tree) are connected by a single node. The UPGMA algorithm does not make any such assumptions as to linear descent, and it simply measures the amount of divergence among populations. The branches between SX and LC ducks are deep, and are well supported by bootstrap values, indicating an unam- biguous genetic distance between them.
The highest grain yield was observed at 120 days after sowing in BD 725 (3.58 t ha -1 ). However, the lowest grain yield was observed at 120 days after sowing in BD 728 (2.42 t ha -1 ). Genotypic variations play an important role in determining the yield of crops and the potential of genotypes within genetic limits is set by its adaptability with the studied area. Al–Lahham, et al., (2013) reported that the variation in grain yield among the cultivars may be attributed to many factors including the availability of nutrient in the soil and the gene responsible for the nutrient uptake. Bucheyeki et al. (2010) also found the similar genetic variation on yield.
Plant Improvement Institute research center in Karaj. In order to calculate the error and correct the collected data, four wheat cultivars of Sivand, Pishtaz, Pishgam, and Sirvan with three replications were used as control groups. The control group was cultivated based on augmented design and genotypes were placed in separate blocks among the control groups. The treatments and control groups were divided into three blocks and each block containing 60 plots which were planted on one-meter beds and the spacing between each plot from other plot was considered 62 cm. The necessary measurements and samples of the movement were collected systematically and by observationally method and sampling from the statistical population of each plot. Data analysis, statistical analyzes of multivariate data including cluster analysis based on multivariate analysis such as principal component analysis (PCA) and simple correlation analysis between characteristics (Pearson) are done using statistical software SPSS and SAS.
Comparison to ADMIXTURE: Both nonspatial conStruct and ADMIXTURE displayed the successive partitioning of space and the clines of admixture seen in the simulation results. The details of each were somewhat different (Figure S20 vs. Figure S24), and also differed across the replicate analyses. These differences between runs and methods may be due to noise in the different inference algorithms employed, multi-modality in the likelihood surfaces, or to model details (e.g., the priors used in nonspatial conStruct, or the fact that ADMIXTURE is modeling each allele’s frequency in each cluster, rather than the covariance across all alleles). However, overall, the be- havior of both methods was quite similar: each recovered the trichocarpa/balsamifera split with the ﬁrst two clusters mod- eled, then, with higher values of K, used subsequent clusters to subdivide the trichocarpa samples into geographically restricted foci of cluster membership. Both nonspatial con- Struct and ADMIXTURE strongly favored the most cluster- rich model (Figure 6 and Figure S25). In contrast, the spatial conStruct model clearly did not favor the model with the
Bayesian clustering analysis showed no obvious sub- division at the population level (results not shown). We explored K values between 1 and 10. For K = 3, corre- sponding lnP(D) was greatest, and the peak of ΔK was highest (see Fig. 1). To determine whether the H. contor- tus populations comprised a single panmictic population with a high degree of gene flow, an analysis of molecular variance (AMOVA) among populations was conducted (Table 3). An analysis using the STRUCTURE program supported the division of H. contortus populations into three groups: group 1 (Guangxi, Hubei and Yunnan), group 2 (Heilongjiang, Liaoning and Shaanxi) and group 3 (Inner Mongolia). Most (96.1%) of the genetic vari- ation was distributed within populations: 3.3% of vari- ance components among groups (F CT ) and 0.6% of
The highest average abundances of Lanice were found in the lowest intertidal zone and in all years more than 90% of all Lanice were situated in the three zones closest to the low tide line (below –0.5 m MTL). These results are in accordance with other studies from the Wadden Sea where high densities of Lanice were restricted to areas below MTL (Wohlenberg 1937; Ziegelmeier 1952; Beukema 1985; Reise 1985; Carey 1987). Abundances gradually decreased in a landward direction. While La- nice was almost absent in the highest intertidal zone in three out of the four years, an average abundance of about 6 ind m –2 in 1998 indicates that abiotic factors do
We examined geneticpopulation structures of B. platifrons from seeps in the Sagami Bay and vents in the Okinawa Trough in our previous study . Compari- sons of the geneticpopulation structures showed no sig- nificant geneticdifferentiation between the seep and vent populations, indicating high dispersal ability and also high adaptability to the abyssal environments albeit vents and seeps provide deep-sea animals with different habi- tats. Our results, however, were not well supported sta- tistically probably due to genetic heterogeneity in our samples. At that time we could not obtain enough speci- mens from a single locality in the Okinawa Trough and used combined specimens from three different localities. In this study, in order to elucidate dispersal ability and environmental adaptability of deep-sea mussels, we re- evaluate geneticpopulation structures of B. platifrons by use of more than 20 specimens collected since then for each locality. We also presented the first data of geneticpopulation structures for B. japonicus. We analyzed se- quences of the mitochondrial ND4 (NADH dehydro- genase subunit 4) gene, because the gene has relatively fast evolutionary rate and has been used for studies of population genetics in diverse animals such as bivalves, fishes, and snakes [29-31].
The in vivo morpho-physiological responses to GA 3 and kinetin application in Neem (A. indica) are studied during annual reproductive flushes from bud development onwards to seed set. The buds and flowers per inflorescence were higher in kinetin treated branches as compared to control. Protein, total sugars and reducing sugars measured higher following kinetin treatment as compared to GA 3 . GA 3 treatments produced poor flowering response, longer juvenility and low contents of the above biochemical analyses. The enzyme assay of invertase, protease, acid- and alkaline phosphatases matched the biochemical responses to the growth regulator treatments. In control, a shorter regeneration phase leads to lower productivity of floral inflorescence and fruit set. Therefore, it is suggested that the application of kinetin may regulate the reproductive phase resulting in improved morpho-physiological characteristics.
samples were then centrifuged at 14,000 g for 10 min at 4°C and the supernatant was transferred to new tubes. Protein concentrations of the samples were determined using a bicinchoninic acid assay, as above. Samples were diluted to ensure that detection fell within the linear range of detection (2 – 6 μ g μ l −1 ) for the carbonylated protein assay. Each sample had a positive and negative aliquot with equal amounts of protein (4 μ g). Before gel electrophoresis, 3 μ l of 12% SDS was added to each sample, and then 6 μ l of 10 mmol l −1 2-4 DNPH solution (Sigma-Aldrich; D199303, 0.198 g DNPH in 100 ml 2 mol l −1 HCl) was added to each positive aliquot and 6 μ l of 2 mol l −1 HCl was added to each negative aliquot. The samples were incubated at room temperature for 15 min and then 4.5 μ l of neutralization solution (20 mmol l −1 Tris-HCl, 36.7 mmol l −1 glycerol) was added to each sample. Samples were loaded and electrophoresed on a 7.5% polyacrylamide gel. Proteins were then transferred onto a nitrocellulose membrane using the semi-dry transfer method. Membranes were blocked with 2% non-fat milk in Tris-buffered saline with Tween-20 (TTBS; 20 mmol l −1 Tris-HCl, 140 mmol l −1 NaCl, 0.1% Tween-20, pH 7.6) and then incubated in a rabbit anti-DNP primary antibody for 1 h (1:5000 in 2% blocking solution, Sigma-Aldrich D9656) followed by three washes in TTBS. Membranes were then incubated in a goat anti-rabbit HRP secondary antibody for 1 h (1:10,000 in 2% blocking solution, ADI- SAB-300). After washing in TTBS twice and once in TBS, the western blot was developed using Supersignal (Life Technologies, 34080) and then exposed and quantified using a Bio-Rad Imager (Gel Doc XR+ and ChemiDoc XRS+ Systems with Image Lab Software, Bio-Rad Laboratories, Hercules, CA, USA). Carbonylated proteins were calculated by subtracting the intensity of the negative aliquot from the intensity of the positive aliquot. To standardize samples between different gels, a sample of heat- shocked limpet foot tissue was run on every gel to quantify levels of carbonylated protein relative to the same internal standard sample.