Banca de QUALIFICAÇÃO: MARLENILDO FERREIRA MELO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : MARLENILDO FERREIRA MELO
DATA : 04/02/2022
HORA: 08:00
LOCAL: Videoconferência via Google Meet
TÍTULO:

Article 1 – Effect of salicylic and jasmonic acid on nutrient accumulation, photosynthetic pigments and oxidative stress in cherry tomato under saline stress

 

Article 2 – Gas exchange and fruit quality of cherry tomato grown in saline nutrient solution with reverse osmosis brine and sprayed with salicylic acid and jasmonic acid

PALAVRAS-CHAVES:

Keywords 1: reverse osmosis brine, salt stress, Solanum lycopersicum L., water reuse.

Keywords 2: fruit quality, reverse osmosis brine, salt stress, Solanum lycopersicum L., water reuse.

PÁGINAS: 54
RESUMO:

Article 1 – Effect of salicylic and jasmonic acid on nutrient accumulation, photosynthetic pigments and oxidative stress in cherry tomato under saline stress

Abstract: Reusing reverse osmose wastewater is an alternative to cope with water scarcity in semiarid regions. Due to the high concentration of salts in brine, strategies to improve salinity tolerance are essential. Thus, a hydroponic experiment was conducted to investigate the protective role of SA and JA in cherry tomato (Solanum lycopersicum L. cv. Samambaia) under non-saline (2.16 dS m-1), moderate saline (4.50 dS m-1) and severe saline (9.00 dS m-1) growth medium prepared with diluted reverse osmosis brine. 500 M SA and 50 M JA were sprayed exogenously, sole or in combination (SA+JA), and water as control. Results showed that salinity reduced plant growth and productivity, due to oxidative stress caused by the accumulation of Na+ and reduced K+ and Ca2+ in plants tissues, increased lipid peroxidation and cell electrolyte leakage, and reduced photosynthetic pigment content. Foliar spray of SA and JA mitigated damage caused by salt stress by reducing Na+ content and improving membrane integrity, although it did not influence on plant growth and productivity. It can be concluded that adding brine to the nutrient solution reduce cherry tomato growth and productivity, and exogenous SA and JA alleviates salt toxicity.


Article 2 – Gas exchange and fruit quality of cherry tomato grown in saline nutrient solution with reverse osmosis brine and sprayed with salicylic acid and jasmonic acid

Abstract: Saline groundwater is generally the main source of water for human consumption and irrigation in the Brazilian semiarid region, needing to be desalinated before use. Reusing the reverse osmosis brine from the desalination process for irrigation is an alternative to deal with water scarcity in the region, in addition to avoiding its direct disposal into the environment. Due to excessive concentration of salts, brine can be diluted in potable water and salt stress attenuators can be used to mitigate the deleterious effects of salinity on plant growth and productivity. In this sense, cherry tomato plants (Solanum lycopersicum L. cv. Samambaia) were grown hydroponically in nutrient solutions of 2.16, 4.50 and 9.00 dS m-1 prepared with brine diluted in potable water and sprayed with 500 M salicylic acid (SA) and 50 M jasmonic acid (SA), alone or in combination (SA+JA), as salt stress attenuators, and water as control. Gas exchange and fruit quality on orange and red ripening stages were evaluated. Results showed that salinity negatively affected plant photosynthesis and gas exchange and reduced fruit weight and size. On the other hand, salt stress improved fruit flavor and quality by enhancing soluble solids content, acidity, and sugars. Exogenous SA and JA alone alleviated damages caused by moderate salt stress (4.50 dS m-1) on gas exchange, but not when sprayed combined. Application combined was advantageous under severe salinity (9.00 dS m-1). Also, although phytohormone treatment did not counteract the negative effect of salt stress on fruit weight and size, it enhanced fruit acidity, vitamin C content, lycopene, color, and flavor. In conclusion, although saline solution reduced fruit weight and size, it improved fruit quality. Foliar spray of SA and JA alleviated damages caused by salt stress on plant gas exchange and increased fruit quality.

MEMBROS DA BANCA:
Externa à Instituição - MARCIANA BIZERRA DE MORAIS - UERN
Externa à Instituição - MARIA RAQUEL ALCÂNTARA DE MIRANDA - UFC
Presidente - 1632114 - PATRICIA LIGIA DANTAS DE MORAIS