Genetic diversity among ‘Candidatus Liberibacter asiaticus’ isolates based on single nucleotide polymorphisms in 16S rRNA and ribosomal protein genes

2009 ◽  
Vol 59 (4) ◽  
pp. 681-688 ◽  
Author(s):  
Charith Raj Adkar-Purushothama ◽  
Fabio Quaglino ◽  
Paola Casati ◽  
Janardhana Gottravalli Ramanayaka ◽  
Piero Attilio Bianco
2017 ◽  
Vol 12 (5) ◽  
pp. 168
Author(s):  
Muhammad Rizal ◽  
Kikin Hamzah Mutaqin ◽  
Gede Suastika

Huanglongbing also known in Indonesia as citrus vein phloem degeneration (CVPD) is a devastating disease in citrus plantation worldwide, especially in Asia, Africa, and America. In Asian countries including Indonesia, Candidatus Liberibacter asiaticus (CLas) has been confirmed as the causal agent of huanglongbing disease on citrus. Distribution of CLas in Indonesia has been reported in West Borneo, East Nusa Tenggara, Bali, Yogyakarta, Central Java and East Java.  The purpose of this study was to detect CLas in several Indonesia’s citrus plantations that has not and has been reported previously and to study its genetic diversity and their relationship. DNA of plant samples, i.e. citrus leaves, was extracted using CTAB method and CLas was amplified using PCR with the A2/J5 primer pair. DNA amplification results showed that infection of CLas was positively detected from samples from Bogor and Cibodas (West Java), Tuban and Jember (East Java), as well as Katung, Bayung Gede, Kerta, and Pancasari (Bali). Alignment of nucleotide sequences from positive samples showed that their ribosomal protein β-operon has high similiarity to that of CLas OK901 originated from Okinawa (Japan). Isolates of CLas originated from Bogor, Cibodas, Tuban, Jember, and Katung have been known to be identical to other CLas of Indonesian origins reported earlier.  Isolates of CLas originated from Bayung Gede, Pancasari, and Kerta have single nucleotide polymorphisms at 6 points of bases of the 539 total bases compared in their conservative regions, although only 3 of the 6 bases could affect their amino acid sequences. 


2016 ◽  
Vol 141 (1) ◽  
pp. 62-65 ◽  
Author(s):  
Michael J. Havey ◽  
Yul-Kyun Ahn

Garlic (Allium sativum) is cultivated worldwide and appreciated for its culinary uses. In spite of primarily being asexually propagated, garlic shows great morphological variation and adaptability to diverse production environments. Molecular markers and phenotypic characteristics have been used to assess the genetic diversity among garlics. In this study, we undertook transcriptome sequencing from a single garlic plant to identify molecular markers in expressed regions of the garlic genome. Garlic sequences were assembled and selected if they were similar to monomorphic sequences from a doubled haploid (DH) of onion (Allium cepa). Single nucleotide polymorphisms (SNPs) and insertion–deletion (indel) events were identified in 4355 independent garlic assemblies. A sample of the indels was verified using the original complementary DNA (cDNA) library and genomics DNAs from diverse garlics, and segregations confirmed by sexual progenies of garlic. These molecular markers from the garlic transcriptome should be useful for estimates of genetic diversity, identification and removal of duplicate accessions from germplasm collections, and the development of a detailed genetic map of this important vegetable crop.


PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e112968 ◽  
Author(s):  
Thamrongjet Puttamuk ◽  
Lijuan Zhou ◽  
Niphone Thaveechai ◽  
Shouan Zhang ◽  
Cheryl M. Armstrong ◽  
...  

Plant Disease ◽  
2006 ◽  
Vol 90 (10) ◽  
pp. 1360-1360 ◽  
Author(s):  
C.-H. Tsai ◽  
H.-J. Su ◽  
Y.-C. Liao ◽  
T.-H. Hung

Huanglongbing (greening) disease caused by a nonculturable, phloem-limited bacterium is a severe disease of citrus. On the basis of the influence of temperature on host symptoms and the causal agent, this disease can be categorized as Asian caused by “Candidatus Liberibacter asiaticus”, African caused by “Ca. L. africanus”, and American caused by “Ca. L. americanus”. Kumquat (Fortunella margarita (Lour.) Swingle), a member of the Rutaceae is an economically important crop for export and local consumption in Taiwan. Recently, a Huanglongbing-like disease was found on kumquat in Yilan County, the largest kumquat-producing area in northeastern Taiwan. Even though the disease has been reported on Citrus spp. from Taiwan, it has never been reported on kumquat. Symptoms of infected kumquat were mottling, yellowing, hardening, and curling of leaves followed by premature defoliation, twig dieback, decay of feeder rootlets and lateral roots, and ultimately the death of the entire plant. Typical sieve-tube-restricted bacteria were observed in kumquat cells by electron microscopy (1). In addition, psyllid-transmission tests demonstrated that the Asian psyllid (Diaphorina citri) could transmit this bacterium to healthy kumquats. Positive bud graft transmissions were obtained to F. margarita, F. japonica (Thunb.) Swingle, F. obovata Hort. ex Tanaka, Luchen sweet orange (Citrus sinensis (L.) Osb.), and Wentan pummelo (C. maxima f. sp. butan Hay.). These inoculated plants showed symptoms in 3 to 8 months, and bacteria could be detected by polymerase chain reaction (PCR) using a common primer pair that amplified a 226-bp specific DNA fragment (2). For further molecular identification, the bacterial DNA was extracted from the inoculated plants and PCR was performed by using two sets of primers selected from the 16S rRNA region (GenBank Accession No. L22532) and 16S/23S intergenic spacer region (GenBank Accession No. AB019793). The expected DNA fragments of 1,389 bp and 862 bp were, respectively, amplified from symptomatic plants but not from healthy plants. The PCR products were cloned and sequenced (GenBank Accession Nos. DQ302750 and DQ207841). The 16S rRNA has 98 to 99% identity and 16S/23S intergenic spacer region has 99% identity to the corresponding region of “Ca. L. asiaticus” in GenBank. These molecular analyses confirm the presence of “Ca. L. asiaticus” in kumquat. Since Huanglongbing has been rarely reported naturally on kumquat, further analysis of this bacterium as a special strain of “Ca. L. asiaticus” is needed. References: (1) M. Garnier et al. Ann. Microbiol. 135A:169, 1984. (2) T. H. Hung et al. J. Phytopathol. 147:599, 1999.


2020 ◽  
Vol 61 (1) ◽  
pp. 17-23
Author(s):  
Michelle M. Nay ◽  
Stephen L. Byrne ◽  
Eduardo A. Pérez ◽  
Achim Walter ◽  
Bruno Studer

Genomics-assisted breeding of buckwheat (Fagopyrum esculentum Moench) depends on robust genotyping methods. Genotyping by sequencing (GBS) has evolved as a flexible and cost-effective technique frequently used in plant breeding. Several GBS pipelines are available to genetically characterize single genotypes but these are not able to represent the genetic diversity of buckwheat accessions that are maintained as genetically heterogeneous, open-pollinating populations. Here we report the development of a GBS pipeline which, rather than reporting the state of bi-allelic single nucleotide polymorphisms (SNPs), resolves allele frequencies within populations on a genome-wide scale. These genome-wide allele frequency fingerprints (GWAFFs) from 100 pooled individual plants per accession were found to be highly reproducible and revealed the genetic similarity of 20 different buckwheat accessions analysed in our study. The GWAFFs cannot only be used as an efficient tool to precisely describe buckwheat breeding material, they also offer new opportunities to investigate the genetic diversity between different buckwheat accessions and establish variant databases for key material. Furthermore, GWAFFs provide the opportunity to associate allele frequencies to phenotypic traits and quality parameters that are most reliably described on population level. This is the key to practically implement powerful genomics-assisted breeding concepts such as marker-assisted selection and genomic selection in future breeding schemes of allogamous buckwheat. Key words: Buckwheat (Fagopyrum esculentum Moench), genotyping by sequencing (GBS), population genomics, genome-wide allele frequency fingerprints (GWAFFs)   Izvleček Genomsko podprto žlahtnjenje ajde (Fagopyrum esculentum Moench) je odvisno od robustnih metod genotipiziranja. Genotipiziranje s spremljanjem sekvenc (genotyping by sequencing, GBS) se je razvilo kot fleksibilna in razmeroma poceni metoda, ki se jo uporablja pri žlahtnjenju rastlin. Uporabnih je več virov GBS za genetsko karakterizacijo posamičnih genotipov, toda te metode niso primerne za predstavitev genetske raznolikosti vzorcev ajde, ki jih vzdržujemo v heterozigotni obliki, kar velja za odprto oplodne populacije. Tu poročamo o razvoju GBS metode, ki, namesto prikazovanja bi-alelnega polimorfizma posameznih nukleotidov (single nucleotide polymorphisms, SNPs), pokaže frekvence alelov v populaciji na nivoju genoma. Ta prikaz frekvence alelov na nivoju genoma (genome-wide allele frequency fingerprints, GWAFFs) z združenimi sto posameznimi rastlinami vsakega vzorca se je pokazal kot visoko ponovljiv in je prikazal genetsko podobnost 20 različnih vzorcev ajde, ki smo jih analizirali v naši raziskavi. Metoda GWAFFs ni uporabna samo kot učinkovito orodje za natančen opis materiala za žlahtnjenje ajde, ponuja tudi možnosti raziskave  genetskih razlik med različnimi vzorci ajde in omogoča zbirke podatkov. Nadalje, metoda GWAFFs omogoča povezovanje frekvenc alelov s fenotipskimi lastnostmi in kvalitativnih parametrov, ki so najbolj zanesljivo opisani na nivoju populacij. To je ključ za praktično uporabo z genomiko podprtega žlahtnjenja, kot je z genskimi markerji podprta selekcija in genomska selekcija z GWAFFs. Ključne besede: ajda (Fagopyrum esculentum Moench), genotipizacija s sekvenciranjem (GBS), populacijska genomika, GWAFFs


2020 ◽  
Vol 63 (1) ◽  
pp. 193-201
Author(s):  
Heli Xiong ◽  
Xiaoming He ◽  
Jing Li ◽  
Xingneng Liu ◽  
Chaochao Peng ◽  
...  

Abstract. Lanping black-boned sheep was first discovered in the 1950s in Lanping county of China and characterized by black pigmentation on skin and internal organs. Due to the novel and unique trait, the genetic background of Lanping black-boned sheep is of great interest. Here, we genotyped genome-wide SNPs (single nucleotide polymorphisms) of Lanping black-boned sheep and Lanping normal sheep using Illumina OvineSNP50 BeadChip to investigate the genetic diversity and genetic origin of Lanping black-boned sheep. We also downloaded a subset SNP dataset of two Tibet-lineage sheep breeds and four other sheep breeds from the International Sheep Genomics Consortium (ISGC) as a reference for interpreting. Lanping black-boned sheep had a lower genetic diversity level when compared to seven other sheep breeds. Principal component analysis (PCA) showed that Lanping black-boned sheep and Lanping normal sheep were clustered into the Asian group, but there was no clear separation between the two breeds. Structure analysis demonstrated a high ancestry coefficient in Lanping black-boned sheep and Lanping normal sheep. However, the two populations were separated into two distinct branches in a neighbor-joining (NJ) tree. We further evaluated the genetic divergence using population FST, which showed that the genetic differentiation that existed between Lanping black-boned sheep and Lanping normal sheep was higher than that between Tibet sheep and Changthangi sheep, which revealed that Lanping black-boned sheep is a different breed from Lanping normal sheep on the genetic level. In addition, structure analysis and NJ tree showed that Lanping black-boned sheep had a relatively close relation with Tibet sheep. The results reported herein are a first step toward understanding the genetic background of Lanping black-boned sheep, and it will provide informative knowledge on the unique genetic resource conservation and mechanism of novel breed formation.


2021 ◽  
Vol 53 (4) ◽  
pp. 620-631

The Pto gene is a plant gene that has been reported to be involved in resistance to bacterial pathogens. A partial genomic sequence corresponding to Pto (~449 bp) was isolated from 16 species and four hybrids of Phalaenopsis during 2017 at the Department of Agronomy and Horticulture, IPB University, Bogor, Indonesia. Multiple sequence analysis was performed to find putative single nucleotide polymorphisms (SNPs) and design the corresponding single nucleotide-amplified polymorphism (SNAP) markers, which were in turn used to estimate the genetic diversity of 25 Phalaenopsis species. In total, 20 SNPs, of which 14 were nonsynonymous, were identified from the partial Pto sequences. Eighteen SNAP primers were then developed based on these 14 nonsynonymous and four synonymous SNPs. Validation results showed that 15 SNAP primers showed a polymorphism information content exceeding 0.3, suggesting the existence of more than two alleles for this locus. Upon their use, the SNAP markers described 86% of all interspecies variability. The Pto 52, Pto 349, Pto 229, and Pto 380 SNAP markers were very informative in the determination of genetic diversity. Notably, the existence of these nonsynonymous SNPs implied the possibility of functional changes within the amino acid sequence of the putative PTO protein. Thus, the resulting differences in the activity of the PTO protein may be used to breed tolerance to pathogen infection. Further work may be required to establish a functional link between tolerance to pathogens and the presence of Pto-SNAP markers in Phalaenopsis properly.


2009 ◽  
Vol 99 (9) ◽  
pp. 1062-1069 ◽  
Author(s):  
Kenta Tomimura ◽  
Shin-ichi Miyata ◽  
Noriko Furuya ◽  
Kenji Kubota ◽  
Mitsuru Okuda ◽  
...  

The aim of this study was to investigate the genetic diversity and relationships among ‘Candidatus Liberibacter asiaticus’ isolates from different hosts and distinct geographical areas in Southeast Asia. Genetic diversity among ‘Ca. Liberibacter asiaticus’ was estimated by sequencing four well-characterized DNA fragments: the 16S ribosomal DNA (rDNA) and 16S/23S intergenic spacer regions; the outer membrane protein (omp) gene region; the trmU-tufB-secE-nusG-rplKAJL-rpoB region (gene cluster region); and the bacteriophage-type DNA polymerase region. The sequences of the 16S rDNA and 16S/23S intergenic spacer regions were identical among all ‘Ca. Liberibacter asiaticus’ isolates. In contrast, nucleotide substitutions were observed in both the omp gene and the gene cluster regions. However, extended bacteriophage-type DNA polymerase sequences acquired by thermal asymmetric interlaced polymerase chain reaction provided the most sequence diversity among isolates. Phylogenetic analysis of the bacteriophage-type DNA polymerase sequences revealed three clusters in the Southeast Asian ‘Ca. Liberibacter asiaticus’ population. All Indonesian ‘Ca. Liberibacter asiaticus’ isolates clustered in one group. The other clusters were not correlated with geographic distribution. The differences in genetic sequences did not reflect differences in the original citrus host (mandarin or pummelo). These results suggest that the bacteriophage-type DNA polymerase region would be useful for molecular differentiation between different Southeast Asian ‘Ca. Liberibacter asiaticus’ isolates.


Sign in / Sign up

Export Citation Format

Share Document