Exploratory and discriminatory analysis of the phytochemical profile of the aerial part of the species Secale cereale L. Avena strigosa L. and Raphanus sativus L. grown under an agroecological no-tillage system

Abstract

Chemometrics and spectrometry assist characterization and distinction of plant tissue samples
as regards the phytochemical profile. The objective of this study was to perform exploratory and
discriminatory analysis of data obtained by near infrared (NIR) using the R tool, with emphasis
on phenolic profiles discrimination from cover plant species aerial part. Samples of Raphanus
sativus L., Secale cereale L. species were collected at 60, 80 and 100 days after planting, and
at 15 and 30 days after lodging, in an experiment with an agroecological no-tillage system in
the city of Ituporanga, Santa Catarina. The species Avena strigosa L. was collected only at
100 days after sowing and 15 and 30 days after lodging. All data were submitted to principal
component analysis and clustering. Spectral profiles differed in comparison to the cover crop
species used in the cropping system and less in relation to the phenological stage of the plants, and if these species were cultivated singly or consorciated. Exploratory analysis discriminated
the species Raphanus sativus L. from the others in relation to the chemical profile. There was
a discrimination of the samples at 15 days, when all species had already been rolled down in
the field compared to other times.