Masaru Matsumoto

Bio: Masaru Matsumoto is an academic researcher from Kyushu University. The author has contributed to research in topics: Rhizoctonia & Asparagus. The author has an hindex of 12, co-authored 82 publications receiving 451 citations.

Heavy Metal Contamination of Irrigation Water, Soil, and Vegetables and the Difference between Dry and Wet Seasons Near a Multi-Industry Zone in Bangladesh

Abstract: Heavy metal (Cr, Cu, Zn, As, Cd, and Pb) contamination in irrigation water, soil, and vegetables was investigated in farmland adjacent to a multi-industry zone in Bangladesh in dry and wet seasons. In the zone, many factories release wastewater into nearby irrigation canals, and vegetables cultivated with this water could be a major food chain route for human exposure. In the irrigation water and vegetables, heavy metal concentrations exceeded permissible levels in the two seasons, but this was not the case in soil. Zn had the highest concentration, and Cd had the lowest concentration in irrigation water, soil, and vegetables. All heavy metal concentrations were found to be lower in the wet than in the dry season, which is due to the dilution of water by rainfall, lower absorption of heavy metals from the diluted irrigation water, and heavy metal absorption from low concentrated irrigation water and/or soil. The cluster analysis data of irrigation water, soil, and vegetables revealed that the heavy metals in vegetables were considered to be absorbed from irrigation water in the wet season and from soil in the dry season. In the dry season, the high heavy metal concentrations in vegetables might be caused by a high bioconcentration factor (mostly > 20%).

Heavy Metal Contamination of Irrigation Water, Soil, and Vegetables in a Multi-industry District of Bangladesh

Abstract: Heavy metal (Cr, Cu, Zn, As, Cd, and Pb) concentrations in irrigation water, soil, and vegetables were measured to assess the contamination levels in a multi-industry district in Bangladesh. In this district, wastewater discharged from three industrial areas (textile, dye, agrochemical, paint and ceramics factories) was mixed with irrigation water. The Zn, Cu, Pb, and Cr concentrations were high in both irrigation water and soil, and all of these concentrations exceeded the permissible limits except for the Cd and Pb concentrations in irrigation water. Hierarchical cluster analysis of the irrigation water and soil data revealed that the contamination of irrigation water and soil was caused by the discharge of industrial waste into the irrigation water. The heavy metal concentrations in leafy vegetables were mostly below the FAO permissible limits, whereas the As, Cr, and Pb concentrations in root vegetables exceeded the permissible limits. Correlation and cluster analyses of the vegetable data showed that the use of contaminated irrigation water and soil might be responsible for the heavy metal contamination in vegetables. According to the bioconcentration factor (BCF) in root vegetables, the transfer from soil to vegetables of As, Cr, Zn, and Pb was moderate/low, whereas that of Cd and Cu was high. Since these root vegetables were deemed unsafe for human consumption, this type of contamination should be considered more seriously when planting root vegetables.

Comparative de novo transcriptome profiles in Asparagus officinalis and A. kiusianus during the early stage of Phomopsis asparagi infection

Abstract: Asparagus kiusianus, an important wild relative of cultivated asparagus (A officinalis), exhibits resistance to stem blight disease caused by Phomopsis asparagi However, the mechanisms underlying this resistance are not understood and no transcriptomic or genetic resources are available for this species De novo transcriptome sequencing of A officinalis and A kiusianus stems was performed 24 h after inoculation with P asparagi In total, 35,259 and 36,321 transcripts were annotated in A officinalis and A kiusianus, respectively 1,027 up-regulated and 752 down-regulated transcripts were differentially expressed in the two Asparagus species RNA sequencing data were validated using quantitative real-time reverse transcription PCR Several defense-related genes including peroxidase 4, cationic peroxidase SPC4-like, pathogenesis-related protein-1-like, and jasmonic acid biosynthesis and signaling-related genes including phospholipase D alpha 1, 12-oxophytodienoate reductase and jasmonate-induced protein 23 KD were up-regulated in A kiusianus relative to A officinalis In addition, infected A kiusianuns exhibited a substantial increase in jasmonic acid and methyl jasmonate relative to A officinalis Peroxidase activity was significantly elevated in infected A kiusianus compared with infected A officinalis Our transcriptomic database provides a resource for identifying novel genes and molecular markers-associated with Phomopsis disease resistance and will facilitate breeding and improvement of cultivated asparagus varieties

Diversity and occurrence of Burkholderia spp. in the natural environment.

Abstract: Both in natural and in managed ecosystems, bacteria are common inhabitants of the phytosphere and the internal tissues of plants. Probably the most diverse and environmentally adaptable plant-associated bacteria belong to the genus Burkholderia. This genus is well-known for its human, animal and plant pathogenic members, including the Burkholderia cepacia complex. However, it also contains species and strains that are beneficial to plants and can be potentially exploited in biotechnological processes. Here we present an overview of plant-associated Burkholderia spp. with special emphasis on beneficial plant-Burkholderia interactions. A discussion of the potential for utilization of stable plant-Burkholderia spp. associations in the development of low-input cropping systems is also provided.

Sequence variation of the rDNA ITS regions within and between anastomosis groups in Rhizoctonia solani

Abstract: Sequence analysis of the rDNA region containing the internal transcribed spacer (ITS) regions and the 5.8s rDNA coding sequence was used to evaluate the genetic diversity of 45 isolates within and between anastomosis groups (AGs) in Rhizoctonia solani. The 5.8s rDNA sequence was completely conserved across all the AGs examined, whereas the ITS rDNA sequence was found to be highly variable among isolates. The sequence homology in the ITS regions was above 96% for isolates of the same subgroup, 66-100% for isolates of different subgroups within an AG, and 55-96% for isolates of different AGs. In neighbor-joining trees based on distances derived from ITS-5.8s rDNA sequences, subgroups IA, IB and IC within AG-1 and subgroups HG-I and HG-II within AG-4 were placed on statistically significant branches as assessed by bootstrap analysis. These results suggest that sequence analysis of ITS rDNA regions of R. solani may be a valuable tool for identifying AG subgroups of biological significance.

Burkholderia glumae and B. gladioli Cause Bacterial Panicle Blight in Rice in the Southern United States

Abstract: Bacterial panicle blight (BPB) is among the three most limiting rice diseases in Louisiana and the southern United States. The identity and characterization of pathogens associated with this disease was unclear. This research details studies carried out on the pathogens causing BPB on rice in Louisiana and other rice producing southern states. Bacterial strains were isolated from BPB-infected sheath, panicle, or grain samples collected from rice fields in Louisiana, Arkansas, Texas, and Mississippi. In greenhouse inoculation tests, 292 of 364 strains were pathogenic on rice seedlings or panicles. Identification of strains in the pathogen complex by growth on S-PG medium, carbon source utilization profile (Biolog), cellular fatty acid analysis, and polymerase chain reaction (PCR) methods revealed that 76 and 5% of the strains were Burkholderia glumae and B. gladioli, respectively. The other strains have not been conclusively identified. Although strains of both species produced similar symptoms on rice, B. glumae strains were generally more aggressive and caused more severe symptoms on rice than B. gladioli. Virulent strains of both species produced toxoflavin in culture. The two species had similar growth responses to temperature, and optima ranged from 38 to 40°C for B. glumae and 35 to 37°C for B. gladioli. PCR was the most sensitive and accurate method tested for identifying the bacterial pathogens to the species level. The 16S rDNA gene and 16S-23S rDNA internal transcribed spacer (ITS) region sequences of the B. glumae and B. gladioli strains from rice showed more than 99% sequence homology with published sequences. A real-time PCR system was developed to detect and quantify this pathogen from infected seed lots. Our results clearly indicate that B. glumae and B. gladioli were the major pathogens causing BPB in the southern United States.