Application of rep-PCR as a molecular tool for the genetic diversity assessment of Jatropha curcas

Jatropha curcas L., a non-edible Euphorbiaceae oil-rich crop cultivated in subtropical/tropical countries, has gained global attention as a promising renewable resource for biodiesel production. Rep polymerase chain reaction (PCR) was used to investigate the genetic diversity of 15 populations of J. curcas L. Distinct populations of the plant growing wildly in Mauritius were characterised using three molecular markers random-amplified polymorphic DNA (RAPD), repetitive extragenic palindromic (REP), and BOX. Furthermore, to confirm that the amplicons obtained with rep-PCR were derived from mitochondrial genomes, six randomly chosen bands were cloned and sequenced to demonstrate that the amplified products were mitochondrial genome-specific. The average polymorphism information content (PIC) values were 0.329 and the average percentage of polymorphic loci obtained were 89.28 for BOX primer, followed by RAPD (83.41), and REP (55.81) among the different populations with the percentage polymorphic loci ranging from 13.95 to 100. The homology recorded clearly indicated that the amplified products were mitochondrial genome-specific. Rep-PCR provides a quick and cheap method to study diversity at the mitochondrial level in plants.Keywords: Genetic diversity, Jatropha curcas, rep-polymerase chain reaction (PCR

Repetitive element palindromic PCR (rep-PCR) as a genetic tool to study interspecific diversity in Euphorbiaceae family

Background: The classification of diversity in germplasm collections is important for plant breeding. The repetitive element palindromic-polymerase chain reaction (rep-PCR) technique was used to investigate inter-specific diversity within 17 species from the Euphorbiaceae family using REP and BOX primers. Results: The agglomerative cluster analysiswas used to evaluate the scoring data. BOX and REP gave amplification with polymorphism of 98.84% and 100% respectively. REP marker demarcated between the subgenus peltatae. Both markers confirmed Jatropha tanjorensis as a natural hybrid between Jatropha gossypifolia and Jatropha curcas . Five random sequences from the rep-PCR gels were chosen, cloned and sequenced. The blast results demonstrated that the amplified products were from the mitochondrial genomes. Conclusion: The rep-PCR molecular tool can be used to characterize diversity in plants as they are suitable for distinguishing eukaryotic genomes effectively

Early bacterial biofilm colonizers in the coastal waters of Mauritius

Background: The past years have witnessed a growing number of researches in biofilm forming communities due to their environmental and maritime industrial implications. To gain a better understanding of the early bacterial biofilm community, microfiber nets were used as artificial substrates and incubated for a period of 24 h in Mauritian coastal waters. Next-generation sequencing technologies were employed as a tool for identification of early bacterial communities. Different genes associated with quorum sensing and cell motility were further investigated. Results: Proteobacteria were identified as the predominant bacterial microorganisms in the biofilm within the 24 h incubation, of which members affiliated to Gammaproteobacteria, Alphaproteobacteria and Betaproteobacteria were among the most abundant classes. The biofilm community patterns were also driven by phyla such as Firmicutes, Bacteroidetes, Chloroflexi, Actinobacteria and Verrucomicrobia. The functional analysis based on KEGG classification indicated high activities in carbohydrate, lipid and amino acids metabolism. Different genes encoding for luxI, lasI, agrC, flhA, cheA and cheB showed the involvement of microbial members in quorum sensing and cell motility. Conclusion: This study provides both an insight on the early bacterial biofilm forming community and the genes involved in quorum sensing and bacterial cell motility

Jatropha curcas L: Phytochemical, antimicrobial and larvicidal properties

Objective: To evaluate antimicrobial activities as well as the phytochemical and lavicidal properties of different parts of Jatropha curcas L. (J. curcas) growing in Mauritius. Methods: Determination of the presence of phytochemicals in the crude plants extracts by test tube reactions. Disc diffusion method and microdilution method were used to detect the antimicrobial sensitivity and activity (minimal inhibitory concentration). The crude solvent extracts were also tested on the larvae of two insects, Bactrocera zonata and Bactrocera cucurbitae (Diptera, Tephritidae). Results: The antimicrobial activities were significantly dependent for the different crude plant extracts on the thirteen microorganisms tested. For the Gram-positive bacteria, the crude ethyl acetate extract was more efficient compared to the Gram-negative bacteria with both solvents being effective. The crude ethyl acetate extract of J. curcas bark and mature seed oil showed the highest efficacy. The highest mortality percentage was observed after 24 h for both Diptera flies with (66.67 ± 2.89)% of Bactrocera cucurbitae larvae killed by ethyl acetate extract of J. curcas bark. Conclusions: This paper compared the different J. curcas plant sections with respect to the effectiveness of the plant as a potential candidate for new pharmaceuticals. The larvicidal effect was also studied in order to demonstrate the dual purpose of the plant

Repetitive element palindromic PCR (rep-PCR) as a genetic tool to study interspecific diversity in Euphorbiaceae family

Background: The classification of diversity in germplasm collections is important for plant breeding. The repetitive element palindromic-polymerase chain reaction (rep-PCR) technique was used to investigate inter-specific diversity within 17 species from the Euphorbiaceae family using REP and BOX primers. Results: The agglomerative cluster analysis was used to evaluate the scoring data. BOX and REP gave amplification with polymorphism of 98.84% and 100% respectively. REP marker demarcated between the subgenus peltatae. Both markers confirmed Jatropha tanjorensis as a natural hybrid between Jatropha gossypifolia and Jatropha curcas. Five random sequences from the rep-PCR gels were chosen, cloned and sequenced. The blast results demonstrated that the amplified products were from the mitochondrial genomes. Conclusion: The rep-PCR molecular tool can be used to characterize diversity in plants as they are suitable for distinguishing eukaryotic genomes effectively

Dietary intake and lifestyle behaviors of children in Mauritius

The purpose of the study was to explore the dietary intake, fruit, vegetable and energy intake and lifestyle behaviors among Mauritian children. A validated questionnaire was used, assessing dietary intake, mean energy intake, mean body mass index (BMI), lifestyle behaviors as well as nutritional knowledge (NK) among males and females. 336 children aged 6–12 years (165 males and 171 females) from 8 public primary schools were recruited. Statistical analyses revealed that children consumed less nutritious foods such as fruits, vegetables and whole grains and more of refined and calorie-laden foods, with no significant differences across genders. Mean energy intake of children was 1522 ± 282.4 kcal per day while mean BMI was 17.5 ± 4.03 kg/m2. Majority of children had a low-to-moderate physical activity level (PAL), with males being more active than females on average (P = 0.021). 88.7% of children watched TV for more than an hour daily, with 84.8% of them reporting to be eating during the process. Females were more likely to be breakfast skippers (P = 0.003). Maximum frequency of snacking was twice daily (72.7%) while consumption of fast food was once or twice weekly (44.0%). Results indicate the need for intervention with aim of improving the dietary and life quality of children in Mauritius

Multigene Phylogenetics and Morphology Reveal Five Novel Lasiodiplodia Species Associated with Blueberries

Botryosphaeriaceous fungi cause stem blight, canker and dieback in woody plants. During a survey on the fungal pathogens associated with blueberries in China, 135 blighted, cankered or dead blueberry branches were collected from Fujian and Shandong Provinces. Based on the morphological characterization and phylogenetic analyses of a concatenated ITS rDNA, tef1-α, TUB, and RPB2 loci, five new species of Lasiodiplodia, viz., L. clavispora, L. fujianensis, L. henanica, L. nanpingensis and L. paraphysoides were recognized. Detailed descriptions and illustrations, as well as multigene phylogenies, are provided in this paper. The diversity of plant pathogens on agriculturally and economically important plants is higher than anticipated

Multigene phylogenetic analyses to establish new Valsaria species and taxonomic significance of spore ornamentation.

During our studies on fungal diversity from plant substrates, a new species of Valsaria was isolated from dead branches of Ostrya carpinifolia. The taxon is morphologically similar to other taxa in Valsariaceae and is characterized by pseudostromata, apically free pseudoparaphyses, bitunicate asci, and dark brown, 2-celled ascospores. However, it differs from extant species in number of guttules and ornamentation of spore. It is introduced herein as Valsaria ostryae sp. nov. within the family Valsariaceae. Multigene phylogenies based on combined LSU, ITS and RPB2 DNA sequence data generated from maximum likelihood, maximum parsimony and MrBayes analyses indicate that V. ostryae is basal to V. lopadostomoides and V. rudis and its establishment as a new species is strongly supported. No discordance was found between our morphological and phylogenetic species boundaries as postulated by other researchers and our molecular data strongly supports ornamentation of spore as useful for species delineation. Valsaria species do not appear to be host specific. Full morphological details are provided herein and phylogenetic relationships of Valsaria species are also discussed in light with host association