Biology subjects

Gueco, L. S.

Publications and source records attributed to Gueco, L. S..

5 recordsLinked to original sources

bioRxiv2026

The complete chloroplast genome of Garcinia binucao (Blanco) Choisy, an indigenous fruit from the Philippines

Garcinia binucao (Blanco) Choisy is an indigenous species endemic to the Philippines. Its fruit is traditionally used as a souring agent in local cuisine and has been reported to possess nutritional and medicinal properties. Despite its ethnobotanical significance and promising bioactive properties, the species remains underutilized. To date, no genomic resources have been published for G. binucao, limiting its application in food systems, genetic studies, and conservation programs. This study reports the first complete chloroplast genome of G. binucao from an accession conserved at the Institute of Plant Breeding, University of the Philippines Los Banos. The assembled plastome is circular with a length of 156,570 base pairs (bp). It displays the typical quadripartite structure of most angiosperms, consisting of a large single-copy (LSC) region (85,357 bp), a small single-copy (SSC) region (17,129 bp), and a pair of inverted repeats (IR), each 27,042 bp in size. A total of 128 genes were annotated, including 83 protein-coding genes, 37 transfer RNAs (tRNAs), and eight ribosomal RNAs (rRNAs), consistent with the majority of Garcinia species. Of the protein-coding genes, 45 are involved in photosynthesis, 28 genes for self-replication, five genes with conserved open reading frames, and five genes are associated with other functions. The GC content was 36.2%. Leucine (10.6%) was the most abundant amino acid, with a codon usage bias toward UUA. Additionally, 98 simple sequence repeats (SSRs) were detected, 88.78% consisting of A/T motifs. Phylogenomic analysis based on assembled plastome and publicly available cpDNA sequences of 17 other species in the order Malpighiales revealed that G. indica is the closest relative of G. binucao. These findings provide a framework for future research on the species, including its conservation and potential use as a genetic resource.

genomics↗

bioRxiv2025

CHLOROPLAST GENOME AND PHYLOGENETIC ANALYSIS OF KATMON (Dillenia philippinensis Rolfe), A PHILIPPINE ENDEMIC FRUIT

BackgroundKatmon (Dillenia philippinensis Rolfe) is a Philippine endemic fruit species with a relatively well-studied biochemical profile but poor genomic characterization. Studies involving the chloroplast genome can provide valuable insights into its evolution and support conservation efforts. MethodsThe complete chloroplast genome of D. philippinensis was sequenced using Illumina NovaSeqX. Reads were quality-checked, assembled with GetOrganelle, and annotated using CPGAVAS2 and GeSeq. Simple sequence repeats, codon usage, and inverted repeat boundaries were analyzed. Phylogenetic relationships were inferred using concatenated rbcL and matK sequences via maximum likelihood analysis. ResultThe chloroplast genome was 161,591 bp with a GC content of 36.3%. It exhibited the typical quadripartite structure, consisting of a large single-copy region (89,411 bp), a small single-copy region (19,208 bp), and a pair of inverted repeats (26,486 bp each). A total of 113 unique genes were identified, comprising 79 protein-coding, 30 tRNA, and four rRNA genes. Fifty-four SSRs, primarily A/T mononucleotide repeats, and 53,863 codons were observed. Phylogenetic analysis placed D. philippinensis as the closest relative to D. suffroticosa and the most distantly related to D. ovata. The complete chloroplast genome of D. philippinensis provides a valuable resource for phylogenetic studies, germplasm characterization, and future breeding and conservation programs.

plant biology↗

bioRxiv2023

Development and validation of allele specific RLK gene markers for banana bunchy top disease (BBTD) resistance in banana

As global demand for bananas rises, the threat of banana bunchy top disease (BBTD), caused by banana bunchy top virus (BBTV), poses a significant constraint to sustainable banana production. To circumvent this, it is critical to fast-track the development of BBTV-resistant banana cultivars. In a dataset of differentially expressed genes between BBTV-resistant and susceptible bananas, six RLK genes involved in plant defense against pathogens were exclusively upregulated in the BBTV-resistant wild Musa balbisiana compared to the BBTV-susceptible Musa acuminata cv. Lakatan. Here, two genic variants of RLKs, single nucleotide polymorphisms (SNPs) and simple sequence repeats (SSR), were identified in 10 banana accessions representing major genomic groupings. Nine gene-specific markers were developed using three marker systems: SSR, allele-specific PCR, and tetra primer amplification refractory mutation system PCR markers. Six of these were polymorphic and successfully discriminated 117 Musa genotypes at the NPGRL-IPB ex situ germplasm, with an average polymorphism information content of 0.36 for SNP markers and 0.49 for SSR marker, both of which are moderately informative. These markers facilitated the construction of a dendrogram using the Unweighted Neighbor-Joining (UNJ) method with 1000 bootstrap iterations, identifying four major clades: M. acuminata spp. and other Musa spp. (I), wild M. balbisiana (BBw) and other accessions with high-proportion of B-genome (II & III), hybrid bananas (triploids and tetraploids) (IV), which revealed the genetic diversity and relationships among Musa accessions. Ultimately, this genomic resource will aid in positioning the Philippines as a key player in banana disease resistance breeding towards a food-secure banana industry.

genetics↗

bioRxiv2022

Comparative RNA-seq analysis of resistant and susceptible banana genotypes reveals molecular mechanisms in response to Banana bunchy top virus (BBTV)

Banana is a major fruit crop in the Philippines and remains to be a large contributor to the countrys dollar reserve. Among the main hindrances in global banana production, diseases such as Banana bunchy top disease (BBTD) caused by BBTV can bring catastrophic loss to any banana plantation. To elucidate the resistance mechanism and understand the interplay of host factors in the presence of the invading pathogen, we implemented RNA-seq-based comparative transcriptomics analyses of mock- and BBTV-inoculated resistant (wild M. balbisiana) and susceptible (M. acuminata Lakatan) banana genotypes. Similar patterns of expression for 119 differentially expressed genes (DEGs) were observed on both genotypes, representing the typical defense response of banana to BBTV. A set of 173 DEGs specific to the susceptible Lakatan banana cultivar revealed potential host factors and susceptibility mechanisms involved in successful BBTV infection. Further, differential transcriptomic analysis revealed 268 DEGs exclusive to the resistant wild M. balbisiana, unraveling insights into the complex resistance mechanisms involved in BBTV defense such as pathogen perception, phytohormone action, reactive oxygen species (ROS), hypersensitive response (HR), production of secondary metabolites and cell wall modification. The DEGs identified in this study will aid in the design of foreground markers for the precise integration of resistance genes during marker-assisted breeding programs. Furthermore, the application of these results will also enable the foreseen deployment of genome-edited banana cultivars targeting the resistance and host factor genes towards a future-proof banana industry.

genomics↗

bioRxiv2022

Resistance of Musa balbisiana accessions of the Philippines to banana bunchy top virus

Mitigation of banana bunchy top disease (BBTD) is still a challenge worldwide. BBTD is caused by banana bunchy top virus (BBTV), the most important virus affecting banana. Currently, no cultivar or accession of banana has complete resistance to BBTD. A total of 36 wild Musa spp. accessions, including 34 Musabalbisiana and two M. acuminata subsp. errans ( Agutay), were screened for resistance against BBTV. In greenhouse tests using viruliferous banana aphids (Pentalonia nigronervosa), all M. balbisiana accessions remained symptomless and BBTV was not detected in any of these plants by PCR at three- and six-months post inoculation. In contrast, 100% disease incidence was recorded in M. acuminata subsp. errans and in cv. Lakatan susceptible control plants. The PCR-negative M.balbisiana plants were then transferred to a field with high BBTV inoculum pressure where they remained symptomless and PCR-negative for up to five years, while all cv. Lakatan developed BBTD. This study confirmed the resistance of wild M.balbisiana accessions to BBTV. It is therefore expected to provide a resource for conventional and marker assisted breeding.

pathology↗