Genetic diversity of mangrove tree species Avicennia marina in eco-geographic regions of Kerala coast, Southern India

AbstractAvicennia marina (family Acanthaceae) is a halotolerant woody shrub that grows wildly and cultivated in the coastal regions. Despite its importance, the species suffers from lack of genomic datasets to improve its taxonomy and phylogenetic placement across the related species. Here, we have aimed to sequence the plastid genome of A. marina and its comparison with related species in family Acanthaceae. Detailed next-generation sequencing and analysis showed a complete chloroplast genome of 150,279 bp, comprising 38.6% GC. Genome architecture is quadripartite revealing large single copy (82,522 bp), small single copy (17,523 bp), and pair of inverted repeats (25,117 bp). Furthermore, the genome contains 132 different genes, including 87 protein-coding genes, 8 rRNA, 37 tRNA genes, and 126 simple sequence repeats (122 mononucleotide, 2 dinucleotides, and 2 trinucleotides). Interestingly, about 25 forward, 15 reversed and 14 palindromic repeats were also found in the A. marina. High degree synteny was observed in the pairwise alignment with related genomes. The chloroplast genome comparative assessment showed a high degree of sequence similarity in coding regions and varying divergence in the intergenic spacers among ten Acanthaceae species. The pairwise distance showed that A. marina exhibited the highest divergence (0.084) with Justicia flava and showed lowest divergence with Aphelandra knappiae (0.059). Current genomic datasets are a valuable resource for investigating the population and evolutionary genetics of family Acanthaceae members’ specifically A. marina and related species.

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Optimizing Conservation Strategies for a Threatened Tree Species: In Situ Conservation of White Ash (Fraxinus americana L.) Genetic Diversity through Insecticide Treatment

Forests ◽

10.3390/f9040202 ◽

2018 ◽

Vol 9 (4) ◽

pp. 202 ◽

Cited By ~ 9

Author(s):

Charles Flower ◽

Jeremie Fant ◽

Sean Hoban ◽

Kathleen Knight ◽

Laura Steger ◽

...

Keyword(s):

Genetic Diversity ◽

Tree Species ◽

In Situ Conservation ◽

Conservation Strategies ◽

Fraxinus Americana ◽

Insecticide Treatment ◽

White Ash ◽

Threatened Tree Species

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Geographic patterns of genetic diversity in North American trees: a continent-wide analysis

Canadian Journal of Forest Research ◽

10.1139/cjfr-2020-0539 ◽

2021 ◽

Author(s):

Andrew V. Gougherty

Keyword(s):

Genetic Diversity ◽

Population Genetics ◽

North America ◽

North American ◽

Tree Species ◽

Geographic Patterns ◽

Study Characteristics ◽

Dispersal Traits ◽

The Last Glacial Maximum ◽

The Last Glacial

In the northern hemisphere, many species have been reported to have greater genetic diversity in southern populations than northern populations - ostensibly due to migration northward following the last glacial maximum (LGM). The generality of this pattern, while well-established for some taxa, remains unclear for North American trees. To address this issue, I collected published population genetics data for 73 North American tree species, and tested whether genetic diversity was associated with latitude or longitude and whether geographic trends were associated with dispersal traits, range or study characteristics. I found there were no general geographic patterns in genetic diversity, and the strength of the geographic gradients were not associated with any species or study characteristics. Species in the northern and western regions of North America tended to have more species with genetic diversity that declined with latitude, but most species had no significant trend. This work shows that North American trees have complex, individualistic, patterns of genetic diversity that may negate explanation by any particular dispersal trait or range characteristic.

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Genetic Dissimilarity in Conyza sumatrensis Revealed by Simple Sequence Repeat (SSR) Markers

Planta Daninha ◽

10.1590/s0100-83582020380100018 ◽

2020 ◽

Vol 38 ◽

Author(s):

T. SCHNEIDER ◽

M.A. RIZZARDI ◽

S.P. BRAMMER ◽

S.M. SCHEFFER-BASSO ◽

A.L. NUNES

Keyword(s):

Genetic Diversity ◽

Management Strategies ◽

Rapid Evolution ◽

Jaccard Coefficient ◽

Mechanisms Of Resistance ◽

High Genetic Diversity ◽

Resistance To Herbicides ◽

Geographic Regions ◽

Genetic Dissimilarity ◽

Simple Sequence

ABSTRACT: In view of the rapid evolution of Conyza sumatrensis populations resistant to glyphosate, it is necessary to understand the genetic diversity aimed to improve strategies for managing this weed. We investigated the genetic dissimilarity among 15 biotypes of C. sumatrensis from different geographic regions using microsatellite loci. The biotypes, were cultivated in a greenhouse to obtain vegetal material for DNA extraction. Nineteen microsatellite markers (SSR), were developed for C. sumatrensis biotypes. The genetic dissimilarity was estimated by the Jaccard coefficient (JC) and the biotypes grouped by the UPGMA method. The results demonstrated a high dissimilarity (JC = 7.14 to 82.62) of the analyzed material, with the biotypes forming five groups, being one group formed just by the susceptible biotype and in the others grouped by biotypes from distinct locations in the same group The high genetic diversity of C. sumatrensis indicates that the biotypes may show different responses to different management strategies, and that the mechanisms of resistance to herbicides and characteristics of evolution of populations due to adaptability may be some of the factors involved in the genetic variability of the species.

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Intraspecific differentiation of Reed Grass Calamagrostis arundinacea (L.) Roth (Poaceae) populations revealed by peroxidase allozymes

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2008.038 ◽

2011 ◽

Vol 77 (4) ◽

pp. 299-304

Author(s):

Maria Krzakowa ◽

Zbigniew Celka

Keyword(s):

Genetic Diversity ◽

Genetic Parameters ◽

Electrophoretic Analysis ◽

Fixation Index ◽

Mean Values ◽

Interpopulation Variability ◽

Total Genetic Diversity ◽

Variability Level ◽

Hardy Weinberg Equilibrium ◽

Geographic Regions

The genetic Variation of Reed Grass <em>Calamagrostis arundinacea</em> (L.) Roth was investigated in 25 populations in various geographic regions of Poland. A total of 907 individuals were sampled for electrophoretic analysis of peroxidase loci (11 allozymes). Populations were characterised by genetic parameters e.g. heterozygosity level, Wright's fixation index (F) and polymorphism coefficient (Pg). Mean values of interpopulation variability level (GST=0.0310), total genetic diversity (HT=0.4102) and gene flow between populations (Nm=7.805) were also examined. All the populations were polymorphic and they remain in Hardy Weinberg equilibrium.

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On the rebound: soil organic carbon stocks can bounce back to near forest levels when agroforests replace agriculture in southern India

SOIL Discussions ◽

10.5194/soild-2-871-2015 ◽

2015 ◽

Vol 2 (2) ◽

pp. 871-902 ◽

Cited By ~ 3

Author(s):

H. C. Hombegowda ◽

O. van Straaten ◽

M. Köhler ◽

D. Hölscher

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Tree Species ◽

Regional Scale ◽

Clay Fraction ◽

Carbon Stocks ◽

Southern India ◽

Reference Plot ◽

Soc Stock ◽

Soc Stocks

Abstract. Tropical agroforestry has an enormous potential to sequester carbon while simultaneously producing agricultural yields and tree products. The amount of soil organic carbon (SOC) sequestered is however influenced by the type of the agroforestry system established, the soil and climatic conditions and management. In this regional scale study, we utilized a chronosequence approach to investigate how SOC stocks changed when the original forests are converted to agriculture, and then subsequently to four different agroforestry systems (AFSs): homegarden, coffee, coconut and mango. In total we established 224 plots in 56 plot clusters across four climate zones in southern India. Each plot cluster consisted of four plots: a natural forest reference plot, an agriculture reference and two of the same AFS types of two ages (30–60 years and > 60 years). The conversion of forest to agriculture resulted in a large loss the original SOC stock (50–61 %) in the top meter of soil depending on the climate zone. The establishment of homegarden and coffee AFSs on agriculture land caused SOC stocks to rebound to near forest levels, while in mango and coconut AFSs the SOC stock increased only slightly above the agriculture stock. The most important variable regulating SOC stocks and its changes was tree basal area, possibly indicative of organic matter inputs. Furthermore, climatic variables such as temperature and precipitation, and soil variables such as clay fraction and soil pH were likewise all important regulators of SOC and SOC stock changes. Lastly, we found a strong correlation between tree species diversity in homegarden and coffee AFSs and SOC stocks, highlighting possibilities to increase carbon stocks by proper tree species assemblies.

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