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Anand, L.

Publications and source records attributed to Anand, L..

4 recordsLinked to original sources

Grapevine Rootstock and Scion Genotypes' Symbiosis with Soil Microbiome: A Machine Learning Revelation for Climate-Resilient Viticulture

Given the impact of climate change on agriculture, the development of resilient crop cultivars is imperative. A healthy plant microbiota is key to plant productivity, influencing nutrient absorption, disease resistance, and overall vigor. The plant genetic factors controlling the assembly of microbial communities are still unknown. Here we examine if Machine Learning can predict grapevine rootstock and scion genotypes based on soil microbiota, despite environmental variability. The study utilized soil microbial bacteriome datasets from 281 vineyards across 13 countries and five continents, featuring 34 different Vitis vinifera cultivars grafted onto, often ambiguous, rootstocks. Random Forests, Adaptive Boost, Gradient Boost, Support Vector Machines, Gaussian and Bernoulli Naive Bayes, k-Nearest Neighbor, and Neural Networks algorithms were employed to predict continent, country, scion, and rootstock cultivar, under two filtering criteria: retaining sparse classes, ensuring class diversity, and excluding sparse classes assessing model robustness against overfitting. Both criteria showed remarkable F1-weighted scores (>0.8) for all classes, for most algorithms. Moreover, successful rootstock and scion genotype prediction from soil microbiomes confirms that genotypes of both plant parts shape the microbiome. These insights pave the way for identifying plant genes for use with breeding programs that enhance plant productivity and sustainability by improving the plant-microbiota relationship.

plant biology↗

Multi-Omics Insights into Grapevine Dormancy-Budburst Transition: Gene Expression, miRNA Regulation, and DNA Methylation

In grapevine, the transition from a dormant bud to budburst is a critical developmental process related to vegetative and reproductive growth. We generated a time series analysis (five sampling time points) and used transcriptome, small RNA, and whole-genome bisulfite sequencing to characterize this transition. Ecodormant buds took an average of 17 days to budburst. Transcriptome analysis identified a total of 7002 differentially expressed genes across all sampling times and revealed that the brassinosteroid metabolism and the linoleic acid metabolism pathways are upregulated and downregulated respectively across all time points. Gene expression cluster analysis identified the activation of the photosynthesis pathway and photosynthesis related genes during this transition. miRNA expression analysis identified a steady increase in expression of two miRNAs, miR159a and miR159b during the transition from dormancy to budburst. Our analysis suggests that these two miRNAs promote budburst by repressing the expression of auxin responsive genes. Finally, a continued increase in CG methylation levels was observed during the dormancy to budburst transition. Differential methylation analysis, considering dormant buds as the control stage, yielded 6354 differentially methylated regions across the genome. Two glucosidase genes exhibited increases in promoter methylation and a corresponding decrease in gene expression in our analysis. This study provides a multi-omics view of grapevine bud transition from dormancy to bud burst and unveils the interacting genetic and epigenetic networks regulating this process.

plant biology↗

Epigenetic differences between wild and cultivated grapevines highlight the contribution of DNA methylation during crop domestication

The domestication process in grapevine facilitated the fixation of desired traits. The vegetative propagation of grapevines through cuttings has allowed for easier preservation of these genotypes compared to sexual reproduction. Nonetheless, even with vegetative propagation, different phenotypes often emerge within the same vineyard due to potential genetic somatic mutations in the genome. These mutations, however, are not the sole factors influencing phenotype. Alongside somatic variations, epigenetic variation has been proposed as pivotal player in regulating phenotypic variability acquired during domestication. The emergence of these epialleles might have significantly influenced grapevine domestication over time. This study aims to investigate the impact of the domestication process on the methylation patterns in cultivated grapevines. Reduced-representation bisulphite sequencing was conducted on 18 cultivated and wild accessions. Results revealed that cultivated grapevines exhibited higher methylation levels than their wild counterparts. Differential Methylation Analysis between wild and cultivated grapevines identified a total of 9955 differentially methylated cytosines, of which 78% where hypermethylated in cultivated grapevines. Functional analysis shows that core methylated genes (those consistently methylated in wild and cultivated accessions) are associated to stress response and terpenoid/isoprenoid metabolic processes. While genes presenting differential methylation are associated with proteins targeting to the peroxisome, ethylene regulation, histone modifications, and defense response. Additionally, our findings reveal that environmentally induced DNA methylation patterns are, at least partially, guided by the region of origin of wild grapevine accessions. Collectively, our results shed light on the pivotal roles that epialleles might have played throughout the domestication history of grapevines.

plant biology↗

chromoMap: An R package for Interactive Visualization and Annotation of Chromosomes

SummarychromoMap is an R package for constructing interactive visualizations of chromosomes/chromosomal regions, and mapping of chromosomal elements (like genes) onto them, of any living organism. The package takes separate tab-delimited files (BED like) to specify the genomic co-ordinates of the chromosomes and the elements to annotate. Each rendered chromosome is composed of continuous loci of specific ranges where each locus, on hover, displays detailed information about the elements annotated within that locus range. By just tweaking parameters of a single function, users can generate a variety of plots that can either be saved as static image or shared as HTML documents. Users can utilize the various prominent features of chromoMap including, but not limited to, visualizing polyploidy, creating chromosome heatmaps, mapping groups of elements, adding hyperlinks to elements, multi-species chromosome visualization. Availability and implementationThe R package chromoMap is available under the GPL-3 Open Source license. It is included with a vignette for comprehensive understanding of its various features, and is freely available from: https://CRAN.R-project.org/package=chromoMap. Contactlakshayanand15@gmail.com Supplementary informationSupplementary data are available online.

bioinformatics↗