Chiang Mai Journal of Science

     Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (FOC), is a destructive disease that targets the vascular system of banana plants, resulting in wilting and eventual death. FOC can be divided into four physiological races 1, 2, 3, and 4 according to their ability to cause disease, the range of hosts infected, and their genetic traits. FOC Races 1 and 4 have been detected in Southeast Asia. This study used proteomic analysis to identify the stress response proteins involved in the interaction between banana plants and FOC Race 1. These proteins were compared with those previously reported in Race 4 to explore the similarities and differences in plant basal defense response mechanisms against FOC. A total of 758 proteins were identified including 401 in bananas infected with FOC Race 1 and 357 in the control group. Among these, 238 were unique to the control group, while 281 were specific to the FOC Race 1-infected samples. Key stress response-related proteins including β-1,3-glucanase, lipoxygenase, chiti nase, and leucine-rich repeat (LRR) disease resistance proteins exhibited expression patterns consistent with previously reported data. Notable differences were observed in the expression of heat shock proteins (HSPs), especially Hsp70, Hsp90, and stress-response A/B barrel domain-containing proteins. These proteins were predicted to functi on synergisti cally in response to FOC Race 1 infection but acted independently of the jasmonic acid signaling pathway. Our findings suggest that HSPs show potential as an alternative defense mechanism for developing strategies to manage FOC Race 1.

     Optimal precursor volume in aerosol-assisted chemical vapor deposition (AACVD) is crucial for film deposition as it determines the overall performance of devices. This study investigates the influence of precursor volume on tungsten oxide (WO₃) film properties for photoelectrochemical (PEC) water splitting. Tungsten oxide films were deposited at 450 °C using 10, 20, and 30 ml precursor volumes via AACVD. The fabricated photoelectrodes were analyzed for structural, morphological, optical, and PEC performance. The UV-Vis absorption showed that WO3 film prepared using 20 ml precursor volume has the lowest energy bandgap of 2.72 eV. The sample also exhibited the highest photocurrent density of 0.19 mA cm-² at 1.23 V (vs. Ag/AgCl). This result matched the impedance analysis, which demonstrated the lowest charge transfer resistance at electrode-electrolyte interface. This work highlights precursor volume as a critical parameter in AACVD for tailoring WO₃ morphology and PEC activity, providing insights for scalable photoelectrode design.

     Anthracnose is a plant disease that causes significant post-harvest damage to agricultural products. It is primarily caused by fungi of the Colletotrichum genus, which can infect plants at any growth stage. Notably, Colletotrichum can exist in a latent form, infecting immature fruits without showing symptoms until ripening. This leads to undesirable fruit appearance, reduced shelf life, and hindered export potential. This research aimed to develop a Loop-Mediated Isothermal Amplification (LAMP) assay for the detection of anthracnose disease caused by Colletotrichum asianum. Fruits of mango, guava, dragon fruit, and banana showing disease symptoms were collected from markets around Naresuan University and cultured using a tissue transplant technique. The study isolated 11 fungal strains, which were grouped into three categories based on morphological characteristics such as mycelial color and conidial shape. Internal Transcribed Spacer (ITS) sequencing identified five fungal species: three Colletotrichum species (C. musae, C. fructicola, and C. asianum), along with Fusarium incarnatum and Pestalotiopsis sydowiana from other genera. The developed LAMP assay successfully detected C. asianum and C. musae at a constant temperature of 65 °C within 45 minutes. The detection sensitivity for C. asianum was as low as 1 ng/µL of DNA, while C. musae required a minimum of 25 ng/µL. When compared to conventional PCR, the LAMP assay demonstrated up to 10-fold higher sensitivity. In conclusion, the LAMP technique proves to be an efficient and rapid method for detecting anthracnose disease, allowing for more effective disease management and a reduction in post-harvest losses, including those affecting fruit exportation.

     Spherical porous SiO₂ was synthesized via TEOS hydrolysis combined with NaOH etching, and its application in removing heavy metal Cu²⁺ from wastewater was investigated. The morphology, specific surface area, pore structure, and phase of pre- and post-etching SiO₂ were characterized using transmission electron microscopy (TEM), N₂ adsorption analyzer, and X-ray diffraction (XRD), respectively. Additionally, detailed studies were conducted on the adsorption kinetics, isotherms, and thermodynamics, as well as the effects of adsorbent dosage, ionic strength, and pH on Cu²⁺ removal. The results showed that the post-etching SiO₂ (denoted as ESP-SiO₂) presented a porous nanospherical morphology, with significantly larger specific surface area and pore volume compared to the pre-etching sample. Furthermore, the SiO₂ underwent a transformation from an amorphous to a crystalline phase. The adsorption kinetics of Cu²⁺ onto ESP-SiO₂ was well fitted by the pseudo-second-order model, and the adsorption isotherm conformed to the Langmuir model, with a maximum adsorption capacity of 172.41 mg/g. Thermodynamic analysis revealed that the adsorption process was spontaneous, exothermic, and accompanied by an increase in entropy. For a 50 mg/L Cu²⁺ solution, a removal efficiency of 86.5% was achieved when the dosage of ESP-SiO₂ was 0.05 g. Moreover, the material exhibited strong resistance to interference from ionic strength (up to 0.1 mol/L), and the optimal pH for adsorption was 5.5. Given its advantages of low cost, simple preparation, and high removal efficiency, ESP-SiO₂ holds great application potential in the treatment of heavy metal-containing wastewater.