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- Campus Samambaia, Campus Colemar Natal e Silva, Campus Aparecida de Goiânia.
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Genotoxic and Cytotoxic effects of antiretroviral combinations in mice bone marrow
(2016-11) Moraes Filho, Aroldo Vieira de; Carvalho, Cláudia de Jesus Silva; Carneiro, Cristiene Costa; Vale, Camila Regina do; Lima, Débora Cristina da Silva; Carvalho, Wanessa Fernandes; Vieira, Thiago Bernardi; Silva, Daniela de Melo e; Cunha, Kênya Silva; Chen-Chen, Lee
Commonly used guidelines for the management of human immunodeficiency virus (HIV)
infection (highly active antiretroviral therapy, HAART) include drug combinations such as
tenofovir disoproxil fumarate (TDF) + lamivudine (3TC) and combivir [zidovudine (AZT) +
3TC] + efavirenz (EFV). These combinations may enhance the genotoxic effects induced by
such drugs individually, since the therapy requires lifelong adherence and the drugs have
unknown effects during treatment. Thus, the evaluation of the benefits and risks of HAART is
of great importance. In order to assess the cytotoxic and genotoxic potential of three concentrations of each of the antiretroviral combinations TDF + 3TC (800 + 400, 1600 + 800, and
3200 + 1600 mg/kg body weight, BW) and combivir + EFV (200 + 100 + 400, 400 + 200 +
800, and 800 + 400 + 1600 mg/kg BW) after two exposure periods (24 h and 48 h), in the
present study the in vivo comet assay (single-cell gel electrophoresis) and the mouse bone
marrow micronucleus test were used. Neither TDF + 3TC nor combivir + EFV induced DNA
damage at any concentrations tested after 24 h or 48 h using the comet assay. After 24 h,
both combinations increased the micronucleus frequency at all concentrations tested. After
48 h, combivir + EFV increased the micronucleated polychromatic erythrocyte (MNPCE) frequency at the two highest concentrations tested. Polychromatic erythrocytes (PCE)/normochromatic erythrocytes (NCE) ratio was high for both combinations, suggesting that they can
be mitogenic. Since genotoxicity may be related to carcinogenesis, it is necessary to conduct
further studies to verify the long-term mutagenic effects of these drugs.
Root and shoot development of corn seedlings as affected by rhizobacteria
(2022-02) Cruz, Dennis Ricardo Cabral; Nascente, Adriano Stephan; Silva, Mariana Aguiar; Barroso Neto, Juracy
Multifunctional microorganisms are beneficial microorganisms able of promoting plant growth through direct and indirect mechanisms. Because of this, has enormous potential for use when aiming a sustainable agriculture. The objective of this work was to determine the effect of seed inoculation with multifunctional microorganisms on the initial development of corn seedlings. The experiment was carried out under controlled conditions in a completely randomized design, with seven treatments and six replications. Treatments consisted of microbiolization of corn seeds with the rhizobacteria: 1. Burkholderia cepacea (BRM 32111), 2. Serratia marcenses (BRM 32113), 3. Serratia sp. (BRM 32114), 4. Bacillus sp. (BRM 63573), 5. Azospirillum brasilense (Ab-V5), 6. Azospirillum sp. (BRM 63574) and 7. control treatment (no microorganisms). For each experimental unit, 500 mL plastic pots filled with soil and two corn seeds were used. After 14 days the seedlings were removed from the pots, set aside from the ground and photographed with a digital camera. The images presented were analyzed by WinRHIZO 2012 software to determine: total root length, root diameter, total root surface area and root volume. After this, roots and shoots of the seedlings were dried and weighed. Corn seedlings treated with the multifunctional microorganisms Bacillus sp. (BRM 63573), Serratia sp. (BRM32114) and Azospirillum sp. (BRM 63574) presented increased in the root and shoots biomass compared to untreated seeds. The microorganism Azospirillum sp. (BRM 63574) was the one that provided the highest values in the parameters of total root length, root diameter, root volume, root dry mass, shoot dry mass and total dry mass compared to the control treatment. The use of multifunctional microorganisms is a promising alternative to provide greater development of corn seedlings.
Productivity of corn and beans as affected by season and source of nitrogen
(2022-04) Silveira, Pedro Marques da; Nascente, Adriano Stephan; Carvalho, Maria da Conceição Santana
Enhanced-efficiency fertilizers, which provide a reduction in nitrogen (N) losses, can be a viable alternative for the anticipation of topdressing for the moment of sowing, besides reducing operations for the rural producer. This study aimed to determine the effect of the period of application of enhanced-efficiency nitrogen fertilizers on the grain yield of corn and common bean in the Cerrado region in the direct seeding system. The experiment was carried out during two crop seasons (2019/2020 and 2020/2021), under field conditions. The completely randomized blocks experimental design was used, being arranged in a 2x4+1 factorial, with four replicates. Treatments consisted of the combination of the following two periods of nitrogen application: at sowing and recommended (four open leaves of corn and third trefoil in beans); and of the four following types of nitrogen fertilizers: 1. urea + NBPT + Zeolite; 2. urea + B + Cu + Zeolite; 3. Super N; and 4. Urea. Additionally, a control treatment (without N) was included. Nitrogen values for application in the treatments were adjusted so that 150 kg ha-1 N was applied to the corn, cultivated in summer, and 90 kg ha-1 N was applied to the common bean, cultivated in winter. It was concluded that nitrogen sources and period of nitrogen application did not affect corn grain yield, yield components, and common bean grain yield. The application of nitrogen in corn or common bean provided significant increases in crop grain yield.
Bactérias promotoras do crescimento radicular em plântulas de dois cultivares de arroz irrigado por inundação
(2019-04) Sousa, Israel Mendes; Nascente, Adriano Stephan; Filippi, Marta Cristina Corsi de
For growing and development in nature, plants count with the benefits of microorganisms residing in their rhizosphere. Plant growth promoting rhizobacteria (PGPR) are some of these microorganisms that interact in a beneficial way with plant species. Therefore, seed inoculation with PGPR can be an important and sustainable alternative to improve initial development and crop production. The aim was to determine effect of seeds microbiolization with PGPR on root length of flooded lowland rice seedlings. Under controlled conditions, two experiments were conducted with lowland rice cultivars (BRS Catiana and BRS A702 CL) in completely randomized design, with seven treatments and 10 replications. The treatments consisted of six microorganisms: BRM32109 (Bacillus sp.), BRM32110 (Bacillus sp.), BRM32111 (Pseudomonas fluorescens), BRM32112 (Pseudomonas sp.), BRM32113 (Burkholderia pyrrocinia), BRM32114 (Serratia sp.) and a control (no microorganism). Only the cultivar BRS Catiana showed difference among the treatments. The highest root length was presented by the seeds treated with the isolates BRM32110, BRM32112, BRM32109, and BRM32114. Both of cultivars had significance when compared microorganisms to the control. Highlight for seeds of cultivar BRS Catiana, that when treated with the isolates BRM32110 and BRM32112 presented an average increase of 25.7% on the root length, compared to control treatment. For the cultivar BRS A702 CL, all the microorganisms provided increments with average value of 31% in the root length of rice seedlings. Based on the results it can be inferred that PGPR provide significant increases in seedling root length of flooded lowland rice cultivars.
Volatilização da amônia da ureia estabilizada com NBPT na adubação em cobertura da Urochloa ruziziensis
(2018-03) Lima, João Eudes Santana; Nascente, Adriano Stephan; Silveira, Pedro Marques da; Leandro, Wilson Mozena
Urea is the major nitrogen fertilizer used in pastures. In this fertilizer, one of the main nitrogen (N) losses is related to ammonia volatilization. The use of products that provide reduced losses of N from urea can help to increase the use efficiency of this nutrient in pastures. This study aimed to determine the effect of nitrogen sources and doses split applied at topdressing in Urochloa ruziziensis in the N losses by ammonia N-NH3 volatilization. The experiment was conducted in Santo Antônio de Goiás, GO, in a in a Brazilian Oxisol. It was used the randomized blocks experimental design, with four replications, in a factorial arrangement 2 x 5 x 5. Treatments were composed by N sources: common urea and urea with urease inhibitor, N rates: 0, 50, 100, 200 and 300 kg ha-1 (split in 5 applications) and five forage growth period: 11/14 to 12/13 (1º period), 12/14 to 01/12 (2º period), 01/13 to 02/11 (3º period), 03/24 to 04/22 (4º period) and 07/10 to 08/08 (5º period). The use of urea with urease inhibitor provided reductions in ammonia loss by volatilization in comparison to the common urea. Increasing N rates led to increased N-NH3 volatilization. In drier periods of the year it was found greater losses of N by ammonia volatilization.