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Gardoce, R. R.

Publications and source records attributed to Gardoce, R. R..

2 recordsLinked to original sources

Genetic Structure and Diversity of Banana Bunchy Top Virus (BBTV) in the Philippines

Banana bunchy top virus (BBTV) is an important disease of banana in the Philippines and in other banana-producing countries. This study was conducted to investigate the genetic structure and diversity of Philippine BBTV isolates which remain unexplored in the country. BBTV-infected plant tissues were sampled from banana-growing provinces (i.e., Cagayan, Isabela, Quirino, Batangas, Laguna, Rizal, Quezon, Palawan, Cebu, Leyte, and Davao del Sur) and the partial DNA-R gene of BBTV was sequenced. Analysis of all local BBTV isolates showed a nucleotide diversity ({pi}) of 0.00721, average number of nucleotide differences (k) of 5.51984, and haplotype diversity (hd) of 0.971. Neutrality tests using Fus Fs and Tajimas D showed significant and highly negative values which suggest an excess number of rare alleles due to recent population expansion or from genetic hitchhiking. Haplotype network and phylogenetic analyses revealed that the local BBTV isolates were closely related to Southeast Asian (SEA) group and exhibited a monophyletic clade with distinct haplotype grouping from other SEA sequences. However, some Indonesian and Indian reference sequences were also clustered within the Philippine BBTV group suggesting sequence homology. Results also showed that the local BBTV isolates may be categorized into three major haplotype groups (HA, HB, and HC) but only the HC group remained distinct upon comparison with other Philippine and SEA reference sequences. BBTV isolates from Quezon were the most diverse while isolates from Palawan displayed low genetic diversity indices and belonged only in the HC group. The assessment of the degree of variability among Philippine BBTV isolates will provide a reference towards the development of high-throughput BBTV detection systems as well as enable to devise plant breeding strategies to manage the current BBTV spread and variations.

genetics↗

Reference-Aided Full-length Transcript Assembly, cDNA Cloning, and Molecular Characterization of 1 Coronatine-insensitive 1b (COI1b) Gene in Coconut (Cocos nucifera L.)

In the Philippines, 26% of the total agricultural land is devoted to coconut production making coconut one of the most valuable industrial crop in the country. However, the countrys multimillion-dollar coconut industry is threatened by the outbreak of coconut-scale insect (CSI) and other re-emerging insect pests promoting national research institutes to work jointly on developing new tolerant coconut varieties. Here, we report the cloning and characterization of coronatine-insensitive 1 (COI1) gene, one of the candidate insect defense genes, using Catigan Green Dwarf (CATD) genome sequence assembly as reference. Two (2) splicing variants were identified and annotated - CnCOI1b-1 and CnCOI1b-2. The full-length cDNA of CnCOI1b-1 was 7,919 bp with an ORF of 1,176 bp encoding for a deduced protein of 391 amino acids while CnCOI1b-2 has 2,360 bp full-length cDNA with an ORF of 1,743 bp encoding a deduced protein of 580 amino acids. The 3D structural model for the two (2) isoforms were generated through homology modelling. Functional analysis revealed that both isoforms are involved in various physiological and developmental plant processes including defense response of plants to insects and pathogens. Phylogenetic analysis confirms high degree of COI1 protein conservation during evolution, especially among monocot species. Key MessageThis paper reports the molecular cloning and characterization of corononatine-insensitive I (COI1) gene in coconut using reference-guided transcript assembly approach. As a well-known insect defense-response gene in other crops, the results of this study are expected to assist in the development of new resistant coconut varieties as one of the strategies to address threats in coconut production.

genomics↗