Banca de DEFESA: TATIANE SANTOS CORREIA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE: TATIANE SANTOS CORREIA
DATA: 09/05/2025
HORA: 14:00
LOCAL: Anfiteatro do Setor de Fisiologia Vegetal (DBI03) e remotamente
TÍTULO:

Morpho-physiological, nutritional, and yield responses of tomato ethylene-insensitive mutant Never ripe to manganese deficiency

PALAVRAS-CHAVES:

Solanum lycopersicum L.; stress physiology; crop production; nutrient use efficiency

PÁGINAS: 45
GRANDE ÁREA: Ciências Biológicas
ÁREA: Botânica
SUBÁREA: Fisiologia Vegetal
ESPECIALIDADE: Nutrição e Crescimento Vegetal
RESUMO:

Plant growth and development are closely related to nutritional and hormonal factors. Manganese (Mn) is a micronutrient for plants, high doses have toxic effects, while its deficiency reduces productivity and deteriorates the crop. Ethylene is a phytohormone that acts in responses to nutritional stress that limits growth and development. However, little is known about the interaction of ethylene in response to nutritional stress and its impact on metabolic and biochemical levels involved in Mn nutritional stress. The tomato plant (Solanum lycopersicum L. cv. Micro-Tom) mutants for ethylene signaling are more tolerant to nutritional stress. Therefore, the objective of this work was to evaluate the influence of Mn on plant growth and metabolism under conditions of altered ethylene perception. The experiment was conducted in a completely randomized design, comparing 2 genotypes, the wild-type tomato (WT) and its hormonal mutant Never ripe (Nr), and two nutritional stages (absence of Mn and control), totaling 4 treatments. WT and Nr tomato plants were sown in trays with sand and irrigated daily until cotyledon protrusion. Afterward, the seedlings were transferred to 1L pots containing sand, and Hoagland's nutrient solution was applied, with the treatments and the absence of Mn. At the end of the vegetative stage, analyses of chlorophyll fluorescence, gas exchange, and collection for biochemistry were performed. From this collection, pigments, sugars, nitrogen compounds, stress markers and enzymatic activity were quantified. At the end of the experiment, growth and production analyses were performed. For biomass quantification, the plant material was dried and weighed to quantify the dry biomass, which was also used for the determination of nutrient content in the root, stem and leaf. From these values, the total nutrient content, accumulation, and manganese use efficiency were determined. In total, 94 parameters of WT and Nr plants subjected to Mn stress were analyzed. Our results show that WT plants presented more stress-related responses, we can conclude that this behavior is due to the action of ethylene participating in responses related to stress and the absence of Mn through changes in its metabolism, here observed by the increase in root length, root-to-shoot ratio and non-photochemical quenching. On the other hand, plants of the Nr genotype showed better performance in the absence of Mn. We can infer that this was due to the low sensitivity to ethylene, which allowed these plants to maintain their balanced metabolism even under stress due to the absence of Mn, observed here by the accumulation and efficiency in the use of Mn, stomatal conductance, and acquisition of phosphorus and iron.

MEMBROS DA BANCA:
Presidente - VITOR DE LAIA NASCIMENTO (Membro)
Interno - DINORAH MORAES DE SOUZA MARÇAL - UFV (Suplente)
Externo ao Programa - MARIA LIGIA DE SOUZA SILVA - DCS/ESAL (Membro)
Externo à Instituição - FELIPE KLEIN RICACHENEVSKY - UFRGS (Suplente)
Externo à Instituição - CLEBERSON RIBEIRO - UFV (Membro)