Banca de DEFESA: DAVID CABRAL MACEDO
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.DISCENTE : DAVID CABRAL MACEDO
DATA : 19/02/2020
HORA: 09:00
LOCAL: Sala 1
TÍTULO:
Evaluation of common bean genotypes behavior under severe and moderate deficit
PALAVRAS-CHAVES:
Water deficit, Chlorophyll a fluorescence, Phaseolus vulgaris L.
PÁGINAS: 93
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Fitotecnia
ESPECIALIDADE: Fisiologia de Plantas Cultivadas
RESUMO:
Common bean (Phaseolus vulgaris L.) is one of the world's most important edible grain vegetables. However, about 80% of bean production is affected by water scarcity, drastically reducing crop productivity, which makes the use of materials that achieve a higher yield under water deficit, increasingly indispensable. The aim of this study was evaluate drought tolerance in common bean genotypes through two essays: one in a greenhouse and other in the field. In 2018, the vegetation house essay belonging to the Department of Phytotechnics of the Federal Rural University of Rio de Janeiro (UFRRJ) was carried out. The experiment was conducted in 10 L vessels, using a Kanhapudalf, with three genotypes of common common bean (A285, A222 and Diplomata), in a completely randomized design. The water deficit, in turn, was imposed for eight days until the potential of leaf water (Yw) of one of the genotypes reached -1.5 MPa, considered a limit for recovery of common bean. Chlorophyll a fluorescence analysis and soluble leaf protein content (CPSF) were used to discriminate the genotypes' response to drought. In conclusion, under severe water stress (-1.5 MPa), the Diplomata genotype maintained the Yw, the maximum (Fv/Fm) and the effective (ΦPSII) quantum yield of photossystem II significantly higher compared to the other genotypes, along with a lower alternative non-photochemical dissipation (NPQ), and a higher CPFS, which contributed to its high yield under drought. Moreover, the analysis of the day DFv/Fm and night DFv/Fm was indicative of differences in the intensity and recovery of photoinhibition in genotypes. In 2019, through a trial installed at the Experimental Station of the Department of Crop Science at the Federal Rural University of Rio de Janeiro, Seropédica, Brazil, at drought station (August), the responses of three genotypes of common common bean (A320, Diplomata and Carioca) to moderate water deficit (-0.8 MPa) were evaluated. In this case, the use of the same fluorescence variables used in the first assay, with the addition of the electron transport rate (ETR) were complemented with the evaluation of crop growth variables, such as leaf area index (IAF), crop growth rate (TCC) and net assimilation rate (TAL), in addition to CPFS and production components. The test, in turn, was conducted in a Kanhapudalf under luminous saturation conditions (mean of 900 μmols m-2 s-1) in a 3x2 factorial, with two levels (dry and irrigated) and three factors (A320, Diplomata and Carioca). At the end of the essay, it was observed that Diplomata and A320 genotypes maintained the Yw, Fv/Fm, ΦPSII and ETR during the periods in which the drought was more intense, significantly higher than Carioca, while the latter presented higher values of the NPQ under moderate drought conditions (-0.8 MPa). Finally, even though there is a grain yield (PG) under a significantly higher deficit for A320 and Diplomata in relation to Carioca, a high PG was observed both under water deficit and under irrigation for Diplomata, being therefore more stable even dry, which can be endorsed with the data presented by the IAF, TCC, TAL and CPSF.
MEMBROS DA BANCA:
Externa ao Programa - 2466219 - CAMILA FERREIRA DE PINHO
Presidente - 387258 - CARLOS PIMENTEL
Externo à Instituição - EDERSON DA CONCEIÇÃO JESUS - EMBRAPA
Interno - 387256 - JORGE JACOB NETO
Externa à Instituição - ROSÂNGELA STRALIOTTO - EMBRAPA