Banca de DEFESA: MÁRCIO JOSÉ PEREIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MÁRCIO JOSÉ PEREIRA
DATE: 31/01/2025
TIME: 09:00
LOCAL: Auditório do Prédio Mateus Rosas Ribeiro em formato presencial
TITLE:

Agronomic development and nutrient accumulation in sorghum inoculated with plant

growth-promoting bacteria

KEY WORDS:

phosphorus. microorganisms. nitrogen. productivity. Sorghum.

PAGES: 49
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

The use of plant growth promoting bacteria (PGPB) can be an alternative to provide N and P,

and increase the efficiency of nitrogen and phosphate fertilizers, enhancing the productivity of

sorghum crops. In view of the above, the objective of this study was to evaluate the effect of

inoculating bacterial strains in promoting growth and productivity of forage sorghum. The

experiment was carried out in the field in forage sorghum, using the BRS Ponta Negra variety,

for a period of 104 days. A randomized block experimental design was used, with 8 treatments

and 4 replications, totaling 32 experimental plots. The treatments consisted of a combination of

inoculation of sorghum seeds with two strains of bacteria and mineral fertilization. In the

experiment, eight treatments with inoculants combined with nitrogen fertilization were

evaluated: TA = absolute control; TN = nitrogen control, fertilized with 100% of the

recommended N; B1 = Bacillus megaterium, B2 = Bacillus subtillis, B1 + B2 = B. megaterium

+ B. subtillis, B1 + N = B. megaterium + nitrogen, B2 + N = B. subtillis + nitrogen and B1 +

B2 + N = B. megaterium + B. subtillis, + nitrogen. To perform the inoculation, the sorghum

seeds were conditioned in a beaker, and immediately after, 37 mL of the bacterial adhesive

suspension (1.0 mL per seed) were added, shaken and kept in the adhesive suspension for 12

hours. At 82 days after planting (DAP), the following variables were analyzed: chlorophyll, N

and P contents in the index leaf. At 104 DAP at harvest, the plant height, stem diameter, leaf

area and leaf area index, biomass productivity and accumulation of N and P in the stem, leaves,

panicle and total were evaluated. The data obtained were subjected to analysis of variance

(ANOVA) as a function of the treatments. In the variables with significant effects (F test, p ≤

0.05), it was chosen to apply the Scott Knott comparison test (p ≤ 0.05). The use of B.

megaterium and B. subtillis did not show any effects on the evaluated biometric parameters,

leaf area and leaf area index in relation to the nitrogen control. However, significant increases

were obtained when comparing the use of B. megaterium and B. subtilis associated with N, with

the nitrogen control, there was an increase of 27.18% and 17.43%, respectively, in total

chlorophyll. Positive results also occurred in biomass productivity, the highest MFPA

productivity (64.72 t ha-1) was obtained with the inoculation of B. subtilis associated with

nitrogen fertilizer, with an increase of 22.90% in relation to TN (52.66 t ha-1). The application

of B. megaterium also showed an increase in BFPA (60.45 t ha-1), with an increase of 14.79%

in relation to TN. The inoculation of B. subtilis associated with N allowed the highest total

accumulations of N and P, increases of 28.11% and 34.46% respectively in relation to the

nitrogen control. The inoculation of B. subtilis associated with N promoted greater efficiency

in the absorption of the applied N and P, obtaining superior performance to the nitrogen control,

and consequently allowed greater productivity and greater accumulation of nutrients in the

forage sorghum plants.

COMMITTEE MEMBERS:
Presidente - FERNANDO JOSE FREIRE
Interno - ***.952.028-** - FELIPE JOSÉ CURY FRACETTO - USP
Interna - GISELLE GOMES MONTEIRO FRACETTO
Interno - MARIO DE ANDRADE LIRA JUNIOR