Banca de DEFESA: LUAN RAFAEL DOS SANTOS WANDERLEY

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : LUAN RAFAEL DOS SANTOS WANDERLEY
DATE: 30/08/2023
TIME: 09:00
LOCAL: Prédio de Pós-Graduação em Ciência do Solo
TITLE:

Growth, yield and N-fertilizer recovery of sugarcane under drip fertigation

KEY WORDS:

Nitrogen fertilization. Plant Nutrition. Saccharum spp.

PAGES: 101
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

Sugarcane is one of the main crops in the world due to the economic and socio-
environmental importance linked to food production, renewable energy and the generation of
direct and indirect jobs. The average yield of sugarcane is below potential yield. Water deficit
and nutrient availability are among the main restrictive factors for crop development. N is one
of the nutrients with the greatest impact on sugarcane productivity due to its participation in
metabolic processes linked to development. However, the use efficiency of N-fertilizer is low.
Subsurface drip fertigation allows the distribution of fertilizers throughout the production
cycle. The objective was to quantify the N-fertilizer recovery and the gains in the
development and agro-industrial yield of sugarcane under subsurface drip fertigation. The
experimental design used was randomized blocks with four replications. Doses of 0, 100, 200
and 300 kg ha -1 of N via fertigation system and application of 100 kg ha -1 of N were evaluated.
In treatments with nitrogen fertilization via fertigation (100, 200 and 300 kg ha -1 of N)
microplots were installed in those with enriched fertilizer application to determine the
abundance of 15 N atoms in the plant and in the soil solution and to evaluate the recovery of N-
fertilizer in the period before and after the maximum rate of N-accumulation N. Biometrics,
destructive sampling, and SPAD index were performed to determine biomass production, N
content in plant tissue, and N accumulation. At 308 days after harvest (DAH) the harvest was
performed and the agro-industrial yield was determined. Analyzes of contrasts between
treatments were carried out for biometric parameters, production of plant compartments and
agro-industrial yield. In the period before the maximum rate of N accumulation, the highest
doses of N provided greater N enrichment in the soil and in the plant. The accumulation of
biomass and N showed a Gaussian behavior. N application by fertigation resulted in higher
yield. The highest biomass production results were obtained with 300 kg ha -1 of N by
fertigation. Fertigation benefits the management of N fertilization for sugarcane. The greatest
use of N-fertilizer occurs in the period of greatest stem growth. The period of greatest
precipitation, when associated with the reduction phase of N accumulation, reduced the
efficiency of N fertilization to 8.9%. Fertigation provides the highest development and
productivity of sugarcane.

COMMITTEE MEMBERS:
Presidente - EMIDIO CANTIDIO ALMEIDA DE OLIVEIRA
Interno - FERNANDO JOSE FREIRE
Interno - MARIO DE ANDRADE LIRA JUNIOR
Externo à Instituição - DJALMA EUZEBIO SIMOES NETO - UFRPE
Externa à Instituição - JANE KELLY SILVA ARAUJO