1.Isolation of antagonistic Trichoderma spp. against selected phytopathogenic fungi from the field soils in Kelantan
Laila Naher ; Nurul Hazreen ; Nor Aqilah ; Siti Aminah Binti Mohamed Zaini ; Shafiquzzaman Siddiquee
Malaysian Journal of Microbiology 2017;13(2):73-78
Aims: Trichoderma is a soil borne mycoparasitic fungus which comprises a number of fungal strains that act as
biocontrol agent. In this present study have investigated the diversity of Trichoderma in different cultivated soils in state
of Kelantan. The effectiveness of biocontrol agent of isolated Trichoderm species was evaluated against the
phytopathogen of Pyricularia oryzae, Fusarium oxysporum, and Ganoderma boninense.
Methodology and results: The identification experiment was carried out on the basis of morphological characteristics
as colony appearance, shapes and size of conidia, the branching patterns of conidiophores and phialides. Then, the
effectiveness of biocontrol agent of Trichoderma species against the pathogens was tested in plate assay experiment. A
total of 11 isolates were obtained from three different cultivated soils from Jeli (J), Machang (M) and Pasirmas (P).
Morphological studies data identified as two groups of Trichoderma species as Trichoderma harzianum, and T. koningii.
All the isolates showed the antagonistic activity against the pathogens while T. harzianum strain THMPA1 showed
highest antagonistic activity of 80.00% against P. oryzae and in T. koningii strain TKMPA3 group showed highest
antagonistic activity of 69% against P. oryzae.
Conclusion, significance and impact of study: Among the 11 isolates of Trichoderma, the species of T. harzianum
strain THMPA1 was the best as biocontrol agent against P. oryzae. Thus, diversity of Trichoderma species study is
important to find promising species isolation of Trichoderma species which will be influenced in future to sustainable
crop production and maintain green environment.
2.Optimizing electrochemical DNA biosensors for the detection of avian infectious bronchitis virus
Md. Safiul Alam Bhuiyan ; Gilbert Ringgit ; Zarina Amin ; Ag Muhammad Sagaf Abu Bakar ; Suryani Saallah ; Sharifudin Md. Shaarani ; Shafiquzzaman Siddiquee
Malaysian Journal of Microbiology 2023;19(no.6):651-663
Aims:
The aim of the study is to develop the optimised parameters of electrochemical DNA biosensors for the specific detection of the Infectious Bronchitis Virus (IBV) in chickens. The goal is to further create a highly sensitive and specific biosensor that can be used for on-site monitoring of IBV on poultry farms.
Methodology and results:
In this study, an electrochemical DNA biosensor was developed for detecting a specific sequence in the IBV genome. The process involved attaching a NH2-ssDNA probe to a gold electrode, followed by
hybridization with the target DNA. Various parameters like buffer, pH, scan rate, incubation time, redox indicators and temperature were optimised using cyclic voltammetry. The probe DNA was designed to enhance hybridization efficiency, which was assessed by measuring current signals. The biosensor, under optimal conditions, demonstrated high sensitivity and specificity when tested with different sequences, including complementary, non-complementary and mismatched ones. Cross-reactivity studies against non-IBV viruses showed distinguishable current signals. These findings have implications for developing a portable on-site IBV monitoring device for use on farms.
Conclusion, significance and impact of study
The optimised parameters and specificity of the electrochemical DNA biosensor suggest its potential for the development of a portable device for on-site monitoring of IBV on poultry farms. This device could prove to be a valuable tool for the early detection of IBV, helping to prevent further spread of the disease. However, it's essential to conduct further research to ensure the practicality and accuracy of the biosensor in real-world farm settings.