Banca de DEFESA: ADRIANA DOS SANTOS FERREIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ADRIANA DOS SANTOS FERREIRA
DATE: 15/07/2020
TIME: 14:00
LOCAL: meet.google.com/mxv-hcvu-mjx
TITLE:

MORPHOPHYSIOLOGICAL AND BIOCHEMICAL CHANGES IN SEEDLINGS OF Enterolobium contortisiliquum (Vell.) Morong UNDER ABIOTIC STRESSES

KEY WORDS:

Fabaceae, salinity, water deficit, organic solutes, osmoregulators, seedling production.

PAGES: 67
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
SPECIALTY: Sementes Florestais
SUMMARY:

Enterolobium contortisiliquum (Vell.) Morong is a fast-growing tree species that has multiple purposes, such as medicinal, recovery of degraded areas, manufacture of boats, furniture and boxes in general. The objective of this study was to evaluate the morphophysiological and biochemical changes in E. contortisiliquum seedlings submitted to abiotic stresses. The experiment was carried out at the Academic Unit Specialized in Agricultural Sciences (UAECIA), belonging to the Federal University of Rio Grande do Norte (UFRN), Macaíba, RN - Brazil, in the first half of 2019. The design used was in randomized blocks, with five treatments and four repetitions, with the experimental unit consisting of twenty plants. The experimentation of the different stresses occurred independently. Water stress was performed in the following periods: 0. 4. 8. 12 and 16 days, saline stress was simulated in the following electrical conductivities of irrigation water (CEa): 0.3 (control); 2. 4. 6 and 8 dS.m^-1. Before sowing, pre-germination treatment of overcoming dormancy was performed with the help of sandpaper. As a substrate, a mixture of common soil and tanned bovine manure (1: 1) was used. The evaluations were carried out at 30 days after sowing. The variables evaluated for water and saline stresses were: plant height, number of leaves, leaf area, stem diameter, root length, Dickson quality index, height and dry mass ratio of the aerial part, dry mass of the aerial part aerial, root and total dry mass, besides biochemical tests (total free amino acids, proline, total soluble sugars and starch). The results were submitted to analysis of variance by the F test at 5% probability and, in case of significance, submitted to regression analysis. E. contortisiliquum seedlings obtain greater initial growth in an environment with water availability. The four-day water stress period provides E. contortisiliquum seedlings with better drought tolerance. Osmotically active solutes act positively to minimize damage caused by increased water stress, whose mechanisms may be the main determinants used by plants in this condition. The gradual increase in salinity of the irrigation water was detrimental to the growth and accumulation of dry mass of E. contortisiliquum plants with a marked decrease from the 2 dS.m^-1 threshold. The biochemical mechanism of tolerance to salt stress was due to the increase in amino acids, proline and total sugars, concomitantly with the consumption of starch reserves.

BANKING MEMBERS:
Presidente - 270.392.004-06 - SALVADOR BARROS TORRES - EMPARN
Externo à Instituição - FRANCISCO DE ASSIS DE OLIVEIRA - UFERSA
Externo à Instituição - ALEK SANDRO DUTRA - UFC
Externa à Instituição - CYNTHIA CAVALCANTI DE ALBUQUERQUE - UERN