JOURNAL OF ADVANCES IN BIOLOGY

Does Gamasid mites (Acari, Mesostigmata) observed in oil palm and rubber plantations can be used as indicators of tropical secondary forest soil transformation?

2022-11-24T15:11:16+00:00

The aim of the study was to assess modifications in the community of soil mesostigmatid mites’, as indicator of environment stability with land-use change across 2–4 texturally distinct soils in La Mé and Grand Lahou, Côte d’Ivoire. The fieldwork was carried out in humid period on two study sites: 1– rubber landscape (secondary forest, 7-, 12- and 25-year-old rubber plantations) and 2– oil palm landscape (secondary forest, 13-, 20- and 39-year-old oil palm plantations). Three sampling stands were established in each land-use type and age class, for a total of 24 sampling stands. On each sampling stands, soil cores for Gamasid mite’s extraction were taken at 10 cm soil depth through a 40–50 m transect. Our findings highlighted a drop of mesostigmatid mites’ density (–49% and –52%), species richness (–41% and –40%), and diversity (–35% and –49%), respectively after conversion of the secondary forests into rubber and oil palm plantations. The soil with clayey sandy and clayey textures favored the development of the mesostigmatid mites, particularly in the abundance and species richness of Uropodina. However, the soil with sandy clayey textures improved the abundance and species richness of Gamasina. The mesostigmatid mites’ community was degraded in sandy-textured soils. In light of the Maturity Index values, a better quality of soil and environment was detected in the secondary forests compared to plantations. The results also suggest that the mesostigmatid mites’ community influence the soil nutrients and probably plant productivity indirectly by influencing the populations of their prey.

Optimization of the production of black soldier flies Hermetia Illucens by controlling biological parameters in Côte d'Ivoire

2022-08-14T13:15:53+00:00

This study was conducted at the ENS vivarium located at the UFHB of Cocody in the city of Abidjan in the south of Ivory Coast, with a temperature of about 28° C and a humidity of about 70%. It aimed to study some biological parameters of the black soldier fly Hermetia illucens. For achieve this goal, it was a question of studying the different stages of development of the black soldier fly and also studying the evolution of its growth parameters. The flies were captured, kept in an aviary and observed from the fly stage to the end of the pupal stage (emergence of the first flies). Data on the duration of the different stages of development and the evolution of larval growth parameters (average weight, length, width, Fulton index, length/width ratio, survival and mortality rate of larvae) have been taken. This study revealed that the life cycle of Hermetia illucens is between 31 and 43 days, with an incubation time of eggs that lasts 2 days, a larval phase of 14 days, a pupation of 10 days and a duration of adult life of 8 days on average. In addition, this study reports a low mortality rate of larvae (3.45%), larvae much longer (19.46 mm), wider (6 mm) and plumper.

Pyrimidine Derivatives As Analogues Of Plant Hormones For Intensification Of Wheat Growth During The Vegetation Period

2022-05-27T05:15:27+00:00

Wheat is one of the economically important cereals that are widely used in the agricultural sector of many countries. A very important issue is the development of new effective growth regulators to improve the growth and development of this crop in order to increase its productivity. In our investigations the regulating activity of the synthetic low molecular weight heterocyclic compounds, pyrimidine derivatives on growth and development of wheat (Triticum aestivum L.) variety Tyra was studied. It was found that the use of pyrimidine derivatives in a concentration of 10^-7M in water solution revealed a positive effect on the growth and development of both shoot and root systems of wheat plants during the vegetation period. Comparative analysis of the growth regulating activity of synthetic compounds showed that the activity of pyrimidine derivatives was differentiated and depended on substituents in their chemical structure. The application of pyrimidine derivatives as new effective regulators of growth and development of wheat (Triticum aestivum L.) variety Tyra was proposed.