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Chrysanthemum is among the world's most important ornamental plants because of its high economic and cultural value. Our report is the first to describe the detection of chrysanthemum virus B (CVB) in chrysanthemum leaf samples collected from Thailand, which showed yellowing and mild mottling symptoms. The coat protein sequences of CVB isolated in this study share 95.15% identity with previously characterised CVB isolates. Biological indexing found that CVB induced both local and systemic symptoms in tobacco plants, while petunia displayed systemic symptoms. To improve the rapidity and sensitivity of CVB detection, the loop-mediated isothermal amplification (LAMP) technique was developed. LAMP detection was found to be optimal when incubation was conducted at 65 °C for 45 min, wherein the LAMP reaction demonstrated 106 times higher sensitivity than polymerase chain reaction. To simplify the interpretation of results, we designed the method such that a positive result is clearly indicated based on a change of colour (colourimetry), from pink to yellow, as observed visually and via gel electrophoresis. To our best knowledge, this is the first report on the characterisation of molecular, biological and morphological characteristics of CVB infecting chrysanthemum in Thailand, along with the development of colourimetric RT-LAMP for improving detection efficiency.

Vermicompost (VC) produced by African nightcrawler earthworms (Eudrilus eugeniae) is a natural fertilizer with a rich microbial community. Trichoderma asperelloides PSU-P1 is an effective antagonistic microorganism with multifaceted activity mechanisms. This research aimed to develop Trichoderma-bioenriched vermicompost (TBVC) to promote plant growth and induce the defense response in the Thai rice variety "Chor Khing". T. asperelloides PSU-P1 was tested against Rhizoctonia solani, the pathogen of sheath blight disease, using a dual-culture assay. The results showed that T. asperelloides PSU-P1 effectively inhibited R. solani in vitro growth by 70.48%. The TBVC was prepared by adding a conidial suspension (108 conidia/mL) to vermicompost. The viability of Trichoderma persisted in the vermicompost for 6 months and ranged from 1.2 to 2.8 × 107 CFU/mL. Vermicompost water extracts significantly enhanced seed germination, root length, and shoot length compared to a control group (p < 0.05). Plants that received the TBVC displayed significantly longer shoot and root lengths and higher total chlorophyll content than control plants (p < 0.05). The TBVC induced defense response by increasing the enzyme activity of peroxidase (POD) and polyphenol oxidase (PPO) in comparison with control plants. Rice grown in the TBVC had a significantly reduced incidence of sheath blight caused by R. solani in comparison with control rice (p < 0.05). Furthermore, the fungal community of rice plants was analyzed via the high-throughput next-generation sequencing of the internal transcribed spacer (ITS). The fungal community in the TBVC had greater alpha diversity than the community in the VC. Phylum Ascomycota was dominant in both samples, and a heat map showed that Trichoderma was more prevalent in the TBVC than in the VC. Our results indicate that the enrichment of VC with Trichoderma increases growth, enhances the defense response, and reduces the incidence of sheath blight disease in the Thai rice variety "Chor Khing". [ABSTRACT FROM AUTHOR]

Strawberry anthracnose is a serious disease, and fungicides are currently widely used by farmers. Thus, biological control is a good alternative. This study aims to identify the species of endophytic Streptomyces CINv1 that was previously isolated from Cinnamomum verum J. Presl. and to evaluate its properties as a biocontrol agent, plant growth promoter, and plant colonizing endophyte. This strain was identified by analysis of its 16S rRNA gene sequences, and the result shows 100% similarity to Streptomyces albus CINv1. The CINv1 strain displayed high resistance (81.83%) against Colletotrichum sp. isolate CA0110, as tested by the dual culture technique. Additionally, inhibited pathogen growth on IMA-2 agar was observed under a compound microscope. The results demonstrated swelling, bulbousness, and cytoplasmic aggregation of abnormal hyphal, which were confirmed by SEM as well. Furthermore, the functional media used to evaluate plant growth-promoting properties, including nitrogen fixation, phosphate solubilization, and siderophore production, yielded positive results. Analyses of plant hormones by HPLC found their ability to produce indole-3-acetic acid (IAA). Thus, a biological control trial in greenhouse conditions was conducted by spraying a spore suspension of the strain onto strawberry seedlings once a week, which showed a significant reduction in disease severity. After the seventh spraying, the assessment of the number of leaves and canopy height of the seedling showed significant promotion. In addition, the CINv1 strain established a mutualistic interaction with the plant cells through colonization inter-and intracellularly in strawberry roots, leaves, and petioles. Moreover, using LC-MS/MS to analyze the secondary metabolites of this strain, various groups of compounds were found that could potentially benefit pharmaceutical and agricultural uses. [ABSTRACT FROM AUTHOR]

This investigation was performed to assess the influences of the host‐associated probiotic Bacillus altitudinis B61‐34b (BAA) on growth, immune response and disease resistance to Streptococcus agalactiae in Nile tilapia (Oreochromis niloticus). Fish (25.50 ± 0.52 g fish−1) were distributed into 15 aquaria (150 litres tank−1) at density of 20 fish tank−1. The fish were fed basal diets with BAA inclusions in different concentrations: 0 (BAA1—Control), 106 (BAA2), 107 (BAA3), 108 (BAA4) and 109 (BAA5) CFU ml−1 for 8 weeks. A completely randomized design with three replications was used. The results indicated that BAA administration generated greater (p < 0.05) skin mucus and peroxidase activities compared to the control, with maximum levels recorded in BAA4 and BAA5. Higher serum immunities, such as serum lysozyme, serum peroxidase, complement, phagocytosis and respiratory burst activities were observed in the BAA4 and BAA5 dietary groups compared to the control, BAA1, BAA2 and BAA3 diets. The relative percentage of survival, growth performance and FCR were also significantly higher (p < 0.05) in the BAA4 and BAA5 groups. In conclusion, dietary supplementation of B. altitudinis at 108 CFU ml−1 can improve Nile tilapia's growth performance, skin mucus and serum immunities, and disease resistance. [ABSTRACT FROM AUTHOR]