Saturday, May 6, 2023

Fusarium verticillioides of maize plant: Potentials of propitious phytomicrobiome as biocontrol agents

Abstract

Oluwadara Pelumi Omotayo, Olubukola Oluranti Babalola

Disease outbreaks have been recorded due to exposure to Fusarium verticillioides and fumonisin, a mycotoxin produced by this fungus. F. verticillioides is a fungal pathogen of maize that causes infections, such as wilting and rotting, while contact with its fumonisin derivative manifests in the form of mild to severe illnesses in humans and animals. Maize infection by F. verticillioides causes loss or reduction in expected crop yield, thereby influencing households and nations’ economies. While several efforts have been made to control the pathogenic fungus and its occurrence in the environment, it remains a challenge in agriculture, particularly in maize production. Several microorganisms which are plant-associated, especially those associated with the rhizosphere niche have been noted to possess antagonistic effects against F. verticillioides. They can inhibit the pathogen and tackle its debilitating effects on plants. Hence this study reviews the use of rhizosphere-associated biocontrol agents, such as Bacillus spp., Pseudomonas, Enterobacter, and Microbacterium oleivorans which forms part of the phytomicrobiome in other to prevent and control this toxicogenic fungus. These microorganisms were found to not only be effective in controlling its occurrence on maize plants but are environmentally safe and promote crop yield.


https://www.frontiersin.org/articles/10.3389/ffunb.2023.1095765/full

Comparative study of aflatoxin contamination of winter and summer ginger from the North West Province of South Africa

Abstract

Oluwadara Pelumi Omotayo, Abiodun Olusola Omotayo, Olubukola Oluranti Babalola, Mulunda Mwanza

The presence of mycotoxins in staple food can have adverse effects that result in ill health and associated socio-economic losses. Mycotoxins are naturally occurring toxins produced by certain fungi and can be found in staple food plants such as ginger. Ginger is a renowned medicinal plant that is extensively used for cooking and healing. However, this medicinal plant is with little information about its possible mycotoxins contamination. This study determined the occurrence and prevalence of Aflatoxin B1, B2, G1 and G2 and Ochratoxin A contamination in raw ginger sold around Mahikeng, North West Province, South Africa. Samples were collected purposively from various retailers over winter and summer. The analytical procedure optimized was based on immunoaffinity column cleanup (IAC), followed by High-performance liquid chromatography with fluorescence (HPLC-FLC) detection. ELISA was also used for mycotoxin screening. On HPLC, the limits of detection and quantification for the four Aflatoxins were 3.9 × 10−7-1.4 × 10 -3 and 1.3 × 10-6 - 4.7 × 10-3 for samples collected in winter, and 3.7 × 10−7- 1.4 × 10-3, LOQ 1.2 × 10-6 – 4.6 × 10-3 for the summer samples. The average recoveries at three spiking levels ranged from 62 to 91% for the summer samples and 70–93% for those collected in winter. A linearity was observed for the analytes whose correlation coefficients were within the range of 0.9995 and 1.000 for the winter samples and 0.9995 and 1.000 for those collected in summer. The results showed that the contamination levels, especially for samples collected in summer were greater than the legally permissible limits. The t-test analysis shows that the mean and standard deviation of the four types of Aflatoxins considered were higher in summer than in winter. The findings of the study indicated that ginger, as for all agricultural commodities, are prone to mycotoxin contamination.