Browsing by Author "Okrikata, E."

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    Diversity and Abundance of Insects in and Around Faculty of Agriculture, Shabu-Lafia Campus of Nasarawa State University, Nigeria.
    (Department of Agronomy, Nasarawa State University Keffi, 2018-04-30) Ajayi, Folorunso A.; Okrikata, E.; Allahnana, A.M.
    t The current survey was conducted to give a preliminary inventory on the composition and abundance of insects in and around the shabu-lafia campus of Nasarawa State University, Keffi, Nigeria. Sampling were done weekly from dawn to dusk using sweep net and hand picking techniques from the months of April to August 2017. Insect species recovered were identified in the insect museum of Ahmadu Bello University, Zaria. The composition, relative abundance, frequency of occurrence and, some diversity indices were computed. Insect species with relative abundance ≥ 1 % and frequency of occurrence ≥ 25 % were classified as dominant. A total of 243 individuals from 8 orders, 23 families and, 47 species (9 of which were dominant) were recovered. Members belonging to order orthoptera were the most abundant followed by lepidoptera and coleoptera (relative abundance; 57.19 %, 16.05 % and 14.81 %, respectively). Cantatops asthmaticus and Cantatops annulatus were the most predominant insect species. Even though, order orthoptera was the most diverse (Shannon’s index = 2.438); coleopteran had the highest richness index (Margalef’s index = 3.349). The diversity (Shannon’s index = 3.349), richness index (Margalef’s index = 8.374) and evenness index (Buzas and Gibson’s = 0.662) of the study area were all high. Further work need to be done in the study area by expanding the scope and duration of the study area and also, by employing different sampling techniques.
  • Thumbnail Image
    ItemOpen Access
    Impact of solar heat enhanced by the use of black polypropylene sheets on the development of Callosobruchus maculatus Fabricius (Coleoptera: Chrysomelidae) eggs and germinabilty of cowpea seeds
    (Department of Agronomy, Nasarawa State University Keffi, 2021-02-04) Ajayi, Folorunso A.; Peter, E.; Okrikata, E.; Emmanuel, R.A.L.
    Abstract Post-harvest losses caused by Callosobruchus maculatus is a major constraint to cowpea production and the improper use of synthetic insecticides by most farmers have resulted in environmental, health hazards, and development of insecticide resistance in insects. This study evaluates the efficacy of solar heat treatment using double-layered black polypropylene sheets in suppressing the development of the cowpea bruchid eggs and the effect of the heat absorbed on the germination potential of cowpea seeds. Five pairs of 2 – 3-day old adult C. maculatus were allowed to oviposit for ten days on 50 g cowpea seeds in a glass jar in the laboratory before exposure to 24, 48, 72 and 96 h solar heat treatment regimes. Infested cowpea seeds but not exposed to solarization was set along with the treatments while uninfested cowpea seeds was also set along and used as part of the germinability test. The experiment was laid out in a completely randomized design and treatments were replicated four times. The results showed that there were no significant differences among the number of eggs laid by adult C. maculatus on the cowpea seeds before solar heat treatment. Solar heat treatment of the cowpea seed at 24 h achieved 100% egg mortality of C. maculatus thus preventing adult emergence. The effect of solarization on seed viability showed that there were no significant differences between the infested cowpea seeds exposed to different solar radiation regimes when compared to uninfested cowpea seeds – range; 74% – 99% germination. The results showed that 24 h solar heat exposure of cowpea seeds in double-layered black polypropylene sheets could be the thermal death point of C. maculatus eggs on the seeds in the study area.
  • Thumbnail Image
    ItemOpen Access
    mpact of solar heat enhanced by the use of black polypropylene sheets on the development of Callosobruchus maculatus Fabricius (Coleoptera: Chrysomelidae) eggs and germinabilty of cowpea seeds
    (Department of Agronomy, Nasarawa State University Keffi, 2021-02-02) Ajayi, Folorunso A.; Peter, E.; Okrikata, E.; Emmanuel, R.A.L.; Dattijo, S.A.; Kayode, E.A.
    Post-harvest losses caused by Callosobruchus maculatus is a major constraint to cowpea production and the improper use of synthetic insecticides by most farmers have resulted in environmental, health hazards, and development of insecticide resistance in insects. This study evaluates the efficacy of solar heat treatment using double-layered black polypropylene sheets in suppressing the development of the cowpea bruchid eggs and the effect of the heat absorbed on the germination potential of cowpea seeds. Five pairs of 2 – 3-day old adult C. maculatus were allowed to oviposit for ten days on 50 g cowpea seeds in a glass jar in the laboratory before exposure to 24, 48, 72 and 96 h solar heat treatment regimes. Infested cowpea seeds but not exposed to solarization was set along with the treatments while uninfested cowpea seeds was also set along and used as part of the germinability test. The experiment was laid out in a completely randomized design and treatments were replicated four times. The results showed that there were no significant differences among the number of eggs laid by adult C. maculatus on the cowpea seeds before solar heat treatment. Solar heat treatment of the cowpea seed at 24 h achieved 100% egg mortality of C. maculatus thus preventing adult emergence. The effect of solarization on seed viability showed that there were no significant differences between the infested cowpea seeds exposed to different solar radiation regimes when compared to uninfested cowpea seeds – range; 74% – 99% germination. The results showed that 24 h solar heat exposure of cowpea seeds in double-layered black polypropylene sheets could be the thermal death point of C. maculatus eggs on the seeds in the study area.