Banca de DEFESA: MIDOUIN LIDELIAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MIDOUIN LIDELIAS
DATE: 10/02/2023
TIME: 09:00
LOCAL: Prédio Prof. Mateus Rosas Ribeiro
TITLE:

Use of Plant Growth Promoting Bacteria and Arbuscular Mycorrhiza in Saline Stress mitigation in Maize

KEY WORDS:

Saline Stress. Ethylene. ACC Deaminase. AMF. Co-inoculation.

PAGES: 76
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

The plant under saline stress conditions produces large amounts of ethylene, which affects its growth and development. The objective of this work was to evaluate the effect of inoculation of plant growth promoting bacteria (PGPB) and ACC deaminase producers combined with arbuscular mycorrhizal fungus (AMF) (Rizhopagus clarus) on the growth and development of maize (Zea mays L.) in saline stress conditions. The experiment was carried out in a greenhouse at the Federal Rural University of Pernambuco, organized in randomized blocks, with five replications, with the following treatments: i- ten co-inoculations of PGPB and AMF; ii- three concentrations of NaCl (0, 40 and 80 mM); and iii- two controls with AMF inoculation and without inoculation. The experiment has harvested 53 days after planting. Through this study, plant biometrics, physiological parameters, allocation of salts in shoot of plant by the chemical elements chloride, sodium, potassium, and mycorrhizal colonization have analyzed. The results by separate effects showed that salt stress significantly reduced maize growth and its physiological attributes. However, there was a greater tolerance to saline stress for growth in stem length (SL) with the co-inoculations 28-10+FMA, 43+FMA and 70+FMA, and for stem diameter (SD) with the 43+FMA and 85+FMA co-inoculations when compared to AMF controls and no inoculation. Total leaf area (TLA) and shoot dry mass (SDM) showed greater tolerance to salt stress with the 28-10+FMA and 43+FMA co-inoculations when compared to the AMF control, with significant emphasis on MSPA with the 28-10+FMA co-inoculations compared to the AMF control. Furthermore, co-inoculations of PGPB and AMF increased chlorophyll a fluorescence, tolerant to photosynthetic capacity of photosystem II (PSII) under saline stress. In addition, they kept tolerant the maize plant that showed reduced water potential (Ѱw) and osmotic potential (Ѱs), with emphasis more tolerant on co-inculations 28-10+FMA and 59-3+FMA in the Ѱw and 28-10+FMA in Ѱs compared to AMF controls and without inoculation. Furturmore, PGPB and AMF co-inoculations reduced the electrolyte leakage (EL) when compared to the control without inoculation, except, the 28-10+FMA and 52+FMA co-inoculations that kept the plant tolerant to saline stress, then, the plant was slightly exposed to oxidative stress. For the allocation of salts in shoot of maize, a significant increase in the concentration of Cl-, Na+ and Na+/K+ has observed under saline stress. Furthermore, K+ decreased not significantly with increasing NaCl concentration, and the K+/Na+ ratio significantly decreased with increasing NaCl concentration from 0 to 40 and 80 mM. However, the co-inoculations of PGPB and AMF increased the K+ concentration while reducing the Cl- and Na+ concentration and maintained a considerable K+/Na+ ratio in the shot of maize. In Addition, co-inoculations of PGPB and AMF increased mycorrhizal colonization, which has reduced under saline stress. In the present study, ten bacteria combined with AMF were tested, the best highlighted were 28-10, 43, 70, 85, 59-3 and 52. Therefore, by alleviating salt stress in maize, the co-inoculation of these bacteria with AMF will been tested in experiments with non-sterile soil.

COMMITTEE MEMBERS:
Externo à Instituição - ARTHUR PRUDÊNCIO DE ARAÚJO PEREIRA - UFC
Interno - EDIVAN RODRIGUES DE SOUZA
Presidente - GISELLE GOMES MONTEIRO FRACETTO