Navegando por Autor "Silva, Cláudia Ulisses de Carvalho"

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Efeitos do peróxido de hidrogênio (H2O2) na morfologia e bioquímica de plantas de Lippia grata Schauer submetidas a restrições hídricas
(2022-10-06) Silva Filho, Josias Alexandre da; Silva, Cláudia Ulisses de Carvalho; http://lattes.cnpq.br/7161911278790052; http://lattes.cnpq.br/8117701230694209
Lippia grata belongs to the Verbenaceae family, is native to Brazil found in the phytogeographic domains of the Cerrado and Caatinga, Atlantic Forest and Amazon. It is popularly known as alecrim-da-chapada and alecrim-do-mato, which is widely used as a medicinal product, due to the essential oil present in its leaf trichomes, which have bioactives with antiseptic, antimicrobial, antifungal and antibacterial properties. Because it is located in semi-arid environments, water becomes the main limiting factor for the species, and therefore strategies to mitigate the harmful effects of water deficit have been used, such as the application of signaling molecules (elictors), such as hydrogen peroxide, in order to assist plants in conditions of intensified drought stresses. Taking into account the importance of L. grata and its essential oils, since water deficit can affect its development, the objective of the following study was to evaluate the influence of hydrogen peroxide on the biometric and biochemical parameters in L grata subjected to restriction water For this, the leaves of L. grata plants were sprayed with H2O2 at concentrations of 0μM (control), 0.675μM L-1 and 1.35μM L-1 and then subjected to three irrigation regimes: 25%, 50% and 75% of vessel capacity for 60 days. Where biometric parameters and some osmoregulators were measured. The water restriction allied to the higher concentration of hydrogen peroxide (1.35μM L-1) negatively affected the growth and development of L. grata plants, being expressed in the biometric parameters (impairment of growth and production of branches), dry mass of shoots and increase in proline levels.
Indução de tolerância ao estresse salino em mudas de cana-de-açúcar pré-condicionadas com ácido salicílico
(2018-08-15) Oliveira, Henarmmany Cristina Alves de; Silva, Cláudia Ulisses de Carvalho; http://lattes.cnpq.br/7161911278790052; http://lattes.cnpq.br/6859724202937192
Among all the adverse environmental conditions to which the plants are submitted, the salinity is among the main ones, as it causes a reduction in the yield of the crops. In view of this fact, it is necessary to create methods that favor the adaptation of plants to these conditions, one of them is the application of priming treatments before subjecting them to unfavorable environments. The objective of the present work was to promote tolerance to saline stress in pre-sprouted sugarcane seedlings of the Ridesa variety (RB92579), using salicylic acid (AS) as priming. The experimental design was DIC (completely randomized delimitation), with a factorial scheme of 3 x 3, corresponding to three levels of priming: 0mg L-1, 150mg L-1 and 300mg L-1 and three levels of saline concentrations (0 mM, 25 mM and 50 mM NaCl), where each treatment consisted of six replicates. It was applied (single application) in the plants by spraying, AS following the above treatments and after, after fifteen days the plants received the treatments with NaCl. Biometric data, such as: plant height (ALT), fresh biomass (BFA) and dry matter (BSA) and fresh radicular (BFR) and dry biomass (BSR) were measured every 10 days for 40 days. The levels of chlorophyll a, b, total, carotenoids and malondealdehyde (MDA) were also determined. Saline stress promoted reductions of ALT, BFA, BSA, but did not alter BSR, nor did the photosynthetic pigments. Priming promoted reductions in biometric parameters and increase of chlorophyll b at 300mg L-1 AS. Plants not submitted to salinity but receiving 150 mg L-1 of AS reduced BFR. The application of priming provided reductions in lipid peroxidation (MDA) and the H2O2 content acted with a ROS indication. The application of NaCl in the variety RB92579 of sugarcane did not promote oxidative stress in the plants, as a consequence of the salt stress, possibly this behavior may be associated with the low concentration of NaCl applied to the variety, making it impossible to verify effectively the application of salicylic acid as priming.
Influência da sazonalidade sob o acúmulo de osmorreguladores em Pavonia varians Moric, espécie endêmica da Caatinga
(2022-10-06) Barros, Yasmim Lopes de; Nunes, Larisse Bianca Soares Pereira; Silva, Cláudia Ulisses de Carvalho; http://lattes.cnpq.br/7161911278790052; http://lattes.cnpq.br/5742230717504216; http://lattes.cnpq.br/8411583457051354
The Caatinga is a Seasonally Dry Tropical Forest in Brazil, considered one of the most diverse semi-arid regions in the world, with a high number of endemic species and a high living population that is dependent on forest resources. Despite its importance, this region has been suffering major environmental impacts caused by human actions due to the exacerbated use of its resources. This makes it a vulnerable forest to the effects of climate change, resulting in even longer periods of drought and an increase in temperature that can result in reduced biodiversity and species abundance. In this scenario, plants make use of several mechanisms to avoid desiccation and one of them concerns the accumulation of osmoregulators. Through this knowledge, this work aims to evaluate the performance of osmoregulators in Pavonia varians, an endemic species of the Caatinga, during the dry and rainy season. For this, leaves of P. varians were collected in the field to determine the concentrations of photosynthetic pigments, carbohydrates, sucrose, proteins and proline in relation to the rainy and dry seasons. The data obtained were analyzed via ANOVA and the means compared by the Tukey test 5%. Our results show that the quantification of pigment, carbohydrate, protein and proline contents in the leaves did not vary between the dry and rainy seasons. In addition, we evidenced an accumulation of sucrose in the leaves during the dry period, suggesting its importance as an osmotic adjuster so that the species can remain with leaves during the dry period. Finally, the preference of P. varians for the greater accumulation of sucrose in the leaves as a function of the dry period can be considered an innate behavior of the species.
Influência do cocultivo de bactérias promotoras de crescimento no desenvolvimento morfofisiológico de Canistrum aurantiacum (Bromeliaceae)
(2024-03-07) Ferreira, Esdras de Souza; Silva, Cláudia Ulisses de Carvalho; Oliveira, Henarmmany Cristina Alves de; http://lattes.cnpq.br/6859724202937192; http://lattes.cnpq.br/7161911278790052; http://lattes.cnpq.br/0201835717024585
The reintroduction of vulnerable species is a common practice in ecological conservation and restoration, aiming to address the challenges arising from habitat fragmentation and climate change. However, reintroduction attempts of native plants, such as Canistrum aurantiacum, often encounter difficulties in establishing lasting reproductive populations. A promising approach to improve the success of these reintroductions is co-cultivation with growth-promoting bacteria (GPBs), which can benefit plant development at various stages of cultivation. This study sought to evaluate the impact of GPB co-cultivation on the growth and development of C. aurantiacum seedlings. The experiment was conducted in a greenhouse attached to the Plant Physiology Laboratory (LFP) at the Federal Rural University of Pernambuco (UFRPE), Recife-PE. Seeds of C. aurantiacum were sown in trays containing organic substrate and washed sand. After 90 days, the plants were transplanted into containers containing a mixture of organic substrate and sand, previously sterilized. Five GPB treatments, including a control, with 10 replicates each, were used. The plants were inoculated with bacterial suspension or sterile deionized water and maintained under these conditions for 64 days. Biometric and total chlorophyll content analyses were conducted throughout the experiment. The data obtained were analysed using ANOVA, and the means were compared employing the Tukey test at a 5% significance level. However, no significant differences were observed between the treatments regarding these variables. The results indicate that GPB inoculation had no significant effect on the growth and chlorophyll content of C. aurantiacum during the study period. This finding suggests that other factors, such as interspecific interactions between plants and microorganisms, may have influenced plant development. Therefore, further research is needed to better understand the effectiveness of GPB co-cultivation as a management strategy for vulnerable species in reintroduction programs.
Memorial descritivo
(Universidade Federal Rural de Pernambuco, 2022-11) Silva, Cláudia Ulisses de Carvalho; http://lattes.cnpq.br/7161911278790052