Abstract

 Experiments to determine occurrence of pathogens on grains of cowpea (Vigna unguiculata) and maize (Zea mays) infested by Callosobruchus maculatus (F) and Sitophilus zeamais (Mots) was conducted at the Department of Crop, Soil and Pest Management, Federal University of Technology Akure (FUTA). The cowpea varieties (Oloyin, Sokoto white and Drum) and the maize varieties (SWAN 1 SR, White and yellow maize) were used for the experiment. Two hundred grammes of cowpea and maize grains were infested with 0-48 hrs old adults of Callosobruchus maculatus and Sitophilus zeamais respectively. After 14 days of oviposition, the insects were sieved out and the setup left on the laboratory bench for the emergence of fresh adults. After the emergence of the first generation of insects, ten infested grains were selected and plated to isolate the associated pathogens. Similarly, ten grains were selected after the emergence of the 2nd generation of insects for the isolation of associated pathogens. The results from the study showed that the infested and uninfested grains of cowpea and maize contained several pathogens associated with the grains. The microbial load count of Bacterial increased from 27 Cfu/g to 80 Cfu/g while Fungi increased from 1 Cfu/g to 22 Cfu/g. and yeast increased from 122 Cfu/g to 200Cfu/g with period of infestation. It was also observed that moisture content of the infested cowpea grains increased from 6.32% before infestation to 19.84% after infestation while that of maize grains increased from 7.02 before infestation to 11.95% after infestation which consequently enhanced the proliferation of pathogens on the grains. The pathogens isolated and identified include several species of bacteria (Bacillus cereus, Agrobacterium spp e.t.c), fungi (Fusarium equiseti, F. graminearum e.t.c) and yeasts. Based on the results from the study, it was concluded that pathogens occurred in both the infested and uninfested grains of cowpea and maize. Moisture content increased with infestation which consequently increased the microbial loads on the grains. Therefore, appropriate strategies must be used for the protection of the grains against infestation from the insects.

Keywords: Pathogen; Vigna unguiculate; Zea mays; Callosobruchus maculatus; Sitophilus zeamais

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Citation

Citation: Adebayo RA., et al. "Occurrence of Pathogens on Grains of Cowpea (Vigna unguiculata Walpers) and Maize (Zea mays L) Infested by Callosobruchus maculatus (F.) and Sitophilus zeamais Mots".Acta Scientific Agriculture 4.1 (2020): 15-22.

Copyright

Copyright: © 2020 Adebayo RA., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.