Cerrado: Agricultural and Biological Research

Effect Iron Oxide (Fe2O3) nanoparticles synthesis by Teucrium polium L. on Cryptococcus neformans isolated from environmental sources in Kirkuk city, Iraq

Hussein Abdulrazzaq Abbood — 2024-06-23

This study isolated 60 samples from various locations in Kirkuk, including areas with high numbers of pigeons, and birds, residential backyards where chicken breeding takes place, and chicken selling markets where positive samples for Cryptococcus neoformans were identified. Five antifungals were used in different concentrations (Ketoconazole, Griseofulvin, Fluconazole, Nystatin, Clotrimazole), (0.02 g/mL, 0.04 g/mL, and 0.06 g/mL) the sensitivity of the drug to the spread method against isolates of the Cryptococcus neformans. The results showed that the fungal isolates were sensitive to antifungals. This study showed that nystatin has a greater inhibitory ability and a broad spectrum of activity than other antifungals, while griseofulvin did not show any inhibitory ability. Iron oxide nanoparticles (Fe₂O₃ NPs) are produced by the Teucrium polium L. extract as a reducing agent. We used an X-ray diffraction analysis and an SEM to confirm if these nano-oxides were present. The antifungal properties of Fe₂O₃ NPs against Cryptococcus neformans were investigated by the well diffusion method. With the increase in concentration of (Fe₂O₃ NPs). The diameter of inhibition growth zones of the fungal strains became greater; the Cryptococcus neformans growth inhibition zone was 32. 6 ± 0.6 mm, 31.2 ± 0.6 mm, 26 ± 0.5 mm, 24. 4 ± 0.4 mm and 21 ± 0.3 mm and 17.1 ± 0.0 for concentrations 6 mg/mL, 5 mg/mL, 4 mg/mL, 3 mg/mL, 2 mg/mL and 1 mg/mL respectively. Thus, we can conclude that the concentration of the solution of nanoparticles and antifungals directly affects the ability to inhibit the growth of fungi.

Toxic effect of metals (Al, Cd, Pb, Cr, and Fe) in soybean experiment (Glycine max L.) IPRO technology

Jerônimo Luiz da Silva Neto — 2024-06-20

Soil contamination by heavy metals is a serious environmental and agricultural problem. Among the toxic metals, aluminum, cadmium, lead, chromium, and iron represent production problems for agriculture around the world. This study aimed to evaluate the tolerance to Al, Cd, Pb, Cr, and Fe in the vegetative phase of the NEO 790 IPRO cultivar. Different concentrations of 0, 35, 85, and 125 mg L^-1 were prepared and added to the soil. The parameters evaluated were percentage of germination, plant length, root length, aerial and root fresh mass, and aerial and root dry mass. Al and Cd presented negative results for some vegetative parameters, being toxic at the concentrations evaluated. Positive effects were obtained for Pb and Cr on other morphological parameters, and for the Fe element, it was possible to observe double suitability as a toxic element in high doses (> 85 mg L^-1) and in doses lower than 85 mg L^-1 effect stimulator. The NEO 790 IPRO cultivar proved to be resistant in most of the parameters evaluated at the applied doses.

Application of fungicides in the vegetative stage of soybean [Glycine max (L.) Merrill]: Mini-review

Matheus Rodrigues dos Santos — 2024-06-28

The significant growth of soybean cultivation [Glycine max (L.) Merrill], and the expansion of agriculture throughout Brazil, which occurred during the period of evidence of the industrial policy of import substitution, placed the product as an ideal crop to supply the global demand was growing. Several diseases have already been reported in soybeans, but the incidence and severity depend on some factors, such as climate, cultivars, pathogen inoculum potential, soil structure and fertility, and plant vigor, among others. The disease scenario in soybean crops in Brazil has been changing every year, with an increase in the severity of some diseases, both in the aerial part and those caused by soil-dwelling fungi. The use of resistant cultivars can be adopted and is the most efficient way to control diseases. However, even with adequate management, it is necessary to apply fungicides. For more efficient disease management, it is important to know the effectiveness of the main fungicides used in the crop, in terms of their ability to reduce the progress of the disease in the field; selecting the most efficient fungicides for management. The results of the study demonstrated that fungicides positioned in different application programs reduce the incidence of fungal diseases and improve productivity.