Banca de DEFESA: MARIANA SANTOS SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MARIANA SANTOS SILVA
DATE: 23/02/2022
TIME: 09:00
LOCAL: Plataforma Google Meet
TITLE:

Profile of volatile organic compounds of intercrop cultures of citrus agrosystem in the state of Bahia.

KEY WORDS:

Plant volatile-mediated signalling; Sustainable pest management; Citriculture; Chemical ecology.

PAGES: 147
BIG AREA: Ciências Biológicas
AREA: Botânica
SUBÁREA: Fisiologia Vegetal
SUMMARY:

In plants, volatile organic compounds (VOCs) act in defense against infection, predation and as attractors or repellants for herbivores. Several agricultural pests and pathogenic disease vectors that afflict agriculture are insects that use VOCs in locating and choosing host plants. Citrus farming, an important agricultural practice worldwide, is currently affected by Huanglongbing (HLB), a devastating disease caused by systemic bacteria of the Candidatus Liberibacter genus. Diaphorina citri Kuwayama 1908 is a vector for HLB bacteria. The management of HLB is difficult, costly and population control of D. citri is essential for the management of the disease. Due to the severity of HLB and the adverse effects caused by the intensive use of pesticides, we approach in this work an alternative line of research that aims to understand and use VOCs produced by plants to improve the control of natural populations of D.citri. In Brazil, Bahia, which occupies fourth place in the national ranking of citrus production, is considered a disease-free zone, but the presence of D. citri has been reported in the area and there is an imminent risk of the disease being introduced into its orchards. The citrus industry in Bahia is of a family nature and its common the intercropping of citrus with other agricultural species. In this work, we investigate the profile of VOCs in three intercrops used in citrus farming in Bahia: common bean cv. 'Mulatinho' (Phaseolus vulgaris L.); cassava cv. 'Aipim Eucalyptus' (Manihot esculenta Crantz) and yellow passion fruit cv. 'Flavicarpa' (Passiflora edulis Sims.) genotype Embrapa BGP 418. For this purpose, 3 plants of each species were obtained and each specimen was sampled 3 times. The headspace solid-phase extraction technique (HS-SPME) was used and the compounds were separated by gas chromatography coupled to a mass spectrometer (GC-MS). The identification of analytes was performed by injecting a homologous series of n-alkanes (C7 to C20), calculating the Kovats indices, comparing the mass spectra obtained in the analyzes with NIST spectra and injecting commercial analytical standards. The data obtained were evaluated through principal component analysis (PCA) and hierarchical clustering (HCA). Overall, 24 VOCs were identified in the three species, 21 compounds for yellow passion fruit, 14 for cassava and 20 for common bean. Most of the compounds belonged to the class of aldehydes and alcohols and the species were grouped together in PCA and HCA. Qualitative differences were observed in the VOC profile of the three varieties when compared to VOC profiles described in the literature for the same species. In this work, we also carried out a literature review on the line of research addressed in the study, concluding that HLB is a complex pathosystem, in which the use of natural or synthetic odors in the management of D. citri is affected by several factors. However, progress can already be found on the effects and preferences of D. citri for certain plants and its VOCs involved. Authors point out the need for more research focused on the application of laboratory results in the field and on the functionality of the use of certain chemical products in the daily lives of workers.

BANKING MEMBERS:
Presidente - 1299193 - ALESSANDRA SELBACH SCHNADELBACH
Externo à Instituição - ANTÔNIO SOUZA NASCIMENTO - EMBRAPA
Externo à Instituição - FÁBIO NEVES DOS SANTOS - UNICAMP