Banca de QUALIFICAÇÃO: KLEANE TARGINO OLIVEIRA PEREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : KLEANE TARGINO OLIVEIRA PEREIRA
DATE: 19/08/2022
TIME: 14:00
LOCAL: Laboratório de Análise de Sementes
TITLE:

DISCONTINUOUS HYDRATION CYCLES RELIEVE SALINE STRESS IN SEEDS OF Zea mays L.

 

PRIMING CYCLES WITH SALINE STRESS TOLERANCE ELICITORS IN SEEDS OF Mimosa caesalpiniifolia AND Pityrocarpa moniliformis

KEY WORDS:

Palavras-chave do primeiro trabalho (inglês): Zea mays L. Salicylic acid. gibberellic acid. H2O2. Salinity.

Palavras-chave do segundo trabalho (inglês): Caatinga. Attenuators. Salinity. Water memory.

PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUMMARY:

Resumo do primeiro trabalho (inglês): Salt stress reduces germination and initial seedling growth. Discontinuous hydration cycles induce osmotic tolerance, whose association with stress eliciting agents is unprecedented, especially in corn. Thus, the objective was to evaluate the action of discontinuous hydration cycles with different saline stress elicitors on germination, growth, and osmotic adjustment of maize cultivars. The experiment was carried out in a completely randomized design following a 2 x 7 factorial arrangement, with four replications of 50 seeds. Corn seeds, cv. BR 206 and cv. BRS 5037 Cruzeta were submitted: 0.0 mM of NaCl (control); 250 mM NaCl (Saline Stress); saline stress + three discontinuous hydration cycles (CHD) of seeds in water; salt stress + CHD in gibberellic acid; salt stress + CHD in hydrogen peroxide; salt stress + CHD in salicylic acid; and salt stress + CHD in ascorbic acid. The following variables were evaluated: first germination count, germination, shoot length, root length, shoot dry mass, root dry mass, total dry mass, salinity tolerance index, total soluble sugars, total free amino acids and proline. Salt stress (250 mM of NaCl) reduced germination, growth and biomass accumulation in corn seedlings, with cv. BR 206 more tolerant than the BRS 5037 Cruzeta. CHD benefited corn germination, growth and biomass accumulation under saline stress, mainly by inducing the synthesis of osmoprotectants, especially proline. However, only CHD in gibberellic acid and salicylic acid was able to obtain the osmotic adjustment while preserving the energy of the sugars. The CHDs in gibberellic acid and salicylic acid were more suitable for mitigating salt stress in corn.

 

Resumo do segundo trabalho (inglês): Seed exposure to priming cycles with elicitors may favor the survival of species under saline stress conditions. Thus, the objective was to evaluate the action of priming cycles with different saline stress elicitors on germination, initial growth and osmotic adjustment of two Brazilian forest species. The experiment was carried out in a completely randomized design following a 2 x 12 factorial arrangement, with four replications of 30 seeds. The seeds of the species M. caesalpiniifolia and P. moniliformis were submitted to the following treatments: 0.0 mM NaCl (control); 200 mM NaCl (saline stress); saline stress + 1 cycle of seed priming with water; salt stress + 1 cycle of gibberellic acid priming; saline stress + 1 cycle priming with hydrogen peroxide; saline stress + 1 cycle of priming with salicylic acid; saline stress + 1 cycle of ascorbic acid priming; saline stress + 2 cycles of seed priming with water; salt stress + 2 cycles of gibberellic acid priming; saline stress + 2 cycles of priming with hydrogen peroxide; saline stress + 2 cycles of salicylic acid priming; and salt stress + 2 cycles of ascorbic acid priming. Salt stress (200 mM NaCl) reduced germination, growth and biomass accumulation in seedlings of the species, with P. moniliformis being more tolerant than M. caesalpiniifolia. The priming cycles promoted greater tolerance of the species in salinity conditions, which went from moderately sensitive to moderately tolerant to salinity when submitted to 1 cycle of priming with salicylic acid and 2 cycles of priming in gibberellic acid. A water priming cycle improves P. moniliformis tolerance to salt stress. In M. caesalpiniifolia, 2 cycles of gibberellic acid priming improves salt stress tolerance

BANKING MEMBERS:
Externo à Instituição - HOZANO DE SOUZA LEMOS NETO - UFPI
Externo à Instituição - RÕMULO CARANTINO LUCENA MOREIRA - UFCG
Presidente - 270.392.004-06 - SALVADOR BARROS TORRES - EMPARN