Banca de DEFESA: CLENYA CARLA LEANDRO DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : CLENYA CARLA LEANDRO DE OLIVEIRA
DATE: 15/09/2023
TIME: 13:30
LOCAL: VIDEOCONFERÊNCIA
TITLE:

Generation of rice plants (Oryza sativa L.) capable of metabolizing phosphite as a strategy to enhance phosphorus use efficiency

KEY WORDS:

Phosphite; ptxD; Overexpression; Phosphate fertilization

PAGES: 100
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

Phosphorus is one of the elements that most frequently limits crop yields, especially in highly weathered soils. Its availability in nature, in the soil, and efficient use of fertilizers are constant concerns for sustainable agriculture. The greatest challenge in using phosphate fertilizers is sustaining the growing global population, given that they are a finite, non-renewable resource with unevenly distributed reserves primarily concentrated in a few countries. In light of this scenario, developing strategies for more efficient use of phosphorus in agricultural systems has motivated many researchers in the field of agricultural sciences worldwide. The objective of this study was to produce modified rice plants capable of metabolizing phosphite, converting it into phosphate. In this study, a genetic construct was produced in which the PtxD gene from Pseudomonas stutzeri was synthesized with codon optimization for rice (Oryza sativa L) and placed under the control of the maize ubiquitin 1 promoter, ensuring strong and constitutive gene expression in rice. Embryogenic calli originating from the scutellum of mature rice seeds were infected with Agrobacterium tumefaciens carrying the genetic construct ZmUBIL1:PtxD:t-NOS. The selection marker used was the gene encoding hygromycin phosphotransferase (hpt), an enzyme capable of degrading the antibiotic hygromycin. After selecting resistant calli, 44 transgenic lines were regenerated in vitro, acclimated in a plant growth chamber, and grown in a greenhouse until obtaining seeds from the first generation (T1). During the cultivation of the lines, leaf samples were collected, and DNA was extracted to confirm the transformation, which was achieved through a PCR reaction to amplify the PtxD gene and other segments of the genetic construct. Positive lines were grown again to produce seeds for the second generation (T2) and identify plants homozygous for the construct. The ability of the transformed plants to metabolize phosphite was tested by cultivating them in a nutrient solution containing 0.2 mM phosphite as the sole source of phosphorus. Three lines were selected for their ability to develop satisfactorily in a nutrient solution with phosphite as the sole source of phosphorus.

COMMITTEE MEMBERS:
Interno - 2213075 - EVERALDO ZONTA
Presidente - 2626406 - LEANDRO AZEVEDO SANTOS
Externo à Instituição - LEANDRO MARTINS FERREIRA - IFMT