Variations of Major Glucosinolates in Diverse Chinese Cabbage (Brassica rapa ssp. pekinensis) Germplasm as Analyzed by UPLC-ESI-MS/MS.

In this study, the variability of major glucosinolates in the leaf lamina of 134 Chinese cabbage accessions was investigated using Acquity ultra-performance liquid chromatography (UPLC-ESI-MS/MS). A total of twenty glucosinolates were profiled, of which glucobrassicanapin and gluconapin were identified as the predominant glucosinolates within the germplasm. These two glucosinolates had mean concentration levels above 1000.00 µmol/kg DW. Based on the principal component analysis, accessions IT186728, IT120044, IT221789, IT100417, IT278620, IT221754, and IT344740 were separated from the rest in the score plot. These accessions exhibited a higher content of total glucosinolates. Based on the VIP values, 13 compounds were identified as the most influential and responsible for variation in the germplasm. Sinigrin (r = 0.73), gluconapin (r = 0.78), glucobrassicanapin (r = 0.70), epiprogoitrin (r = 0.73), progoitrin (r = 0.74), and gluconasturtiin (r = 0.67) all exhibited a strong positive correlation with total glucosinolate at p < 0.001. This indicates that each of these compounds had a significant influence on the overall glucosinolate content of the various accessions. This study contributes valuable insights into the metabolic diversity of glucosinolates in Chinese cabbage, providing potential for breeding varieties tailored to consumer preferences and nutritional demands.

RDA-Genebank and Digital Phenotyping for Next-Generation Research on Plant Genetic Resources.

The National Agrobiodiversity Center under the Rural Development Administration (RDA) in Jeonju, Republic of Korea stands as the foremost national genebank in the country. Over the years, the National Agrobiodiversity Center has remained committed to enriching its collection with foreign genetic resources, elevating its status to a world-class plant genetic resources (PGR)- holding genebank. Currently, several steps are being undertaken to improve the accessibility of the collection to national as well as international researchers, improve the data available on the resources, and amend the passport information for the accessions. With the implementation of the Nagoya Protocol, the origin of genetic resources is being highlighted as an important input in the passport information. The RDA-Genebank actively responds to the Nagoya Protocol by supplementing passport data for resources lacking information on their origin. In addition, a large number of conserved resources are continuously multiplied, and agronomic traits are investigated concurrently. With the traditional methods of characterization of the germplasm requiring a significant amount of time and effort, we have initiated high-throughput phenotyping using digital techniques to improve our germplasm data. Primarily, we have started adding seed phenotype information followed by measuring root phenotypes which are stored under agronomic traits. This may be the initial step toward using largescale high-throughput techniques for a germplasm. In this study, we aim to provide an introduction to the RDA-Genebank, to adopted international standards, and to the establishment of high-throughput phenotyping techniques for the improvement of passport information.

The complete chloroplast genome of Capsicum annuum var. glabriusculum using Illumina sequencing.

Chloroplast (cp) genome sequences provide a valuable source for DNA barcoding. Molecular phylogenetic studies have concentrated on DNA sequencing of conserved gene loci. However, this approach is time consuming and more difficult to implement when gene organization differs among species. Here we report the complete re-sequencing of the cp genome of Capsicum pepper (Capsicum annuum var. glabriusculum) using the Illumina platform. The total length of the cp genome is 156,817 bp with a 37.7% overall GC content. A pair of inverted repeats (IRs) of 50,284 bp were separated by a small single copy (SSC; 18,948 bp) and a large single copy (LSC; 87,446 bp). The number of cp genes in C. annuum var. glabriusculum is the same as that in other Capsicum species. Variations in the lengths of LSC; SSC and IR regions were the main contributors to the size variation in the cp genome of this species. A total of 125 simple sequence repeat (SSR) and 48 insertions or deletions variants were found by sequence alignment of Capsicum cp genome. These findings provide a foundation for further investigation of cp genome evolution in Capsicum and other higher plants.

Sensitive and specific detection of phaseolotoxigenic and nontoxigenic strains of Pseudomonas syringae pv. phaseolicola by TaqMan real-time PCR using site-specific recombinase gene sequences.

Pseudomonas syringae pv. phaseolicola, the causative agent of halo blight, is the most important bacterial pathogen of bean. Both nontoxigenic (Tox(-)) and toxigenic (Tox+) strains of this pathogen cause halo blight in beans. However, nontoxigenic strains cannot be detected by currently available molecular and serological tools. In this study, a TaqMan probe and primer set were designed based on the phage integrase family site-specific recombinase of P. s. pv. phaseolicola 1448A because it is known that most site-specific recombinases are structurally and functionally diverse. The specificity of the probe and primers was evaluated using purified DNA from 29 isolates of 3 different pathovars of P. syringae. The probe and primer set were able to detect Tox(-) and Tox+ isolates of P. s. pv. Phaseolicola, but no other phytopathogenic bacteria. The assay was also able to detect at least 5 genome equivalents of cloned amplified target DNA, using purified DNA, or 7 colony forming unit (CFU) per reaction when using calibrated cell suspensions. Thus, the TaqMan real-time PCR-based method can be used for the rapid detection of both types of P. s. pv. Phaseolicola, and will potentially simplify and facilitate the diagnosis and monitoring of this pathogen, and guide plant disease management.