Relationship between vegetation indices and agronomic performance of maize varieties under different nitrogen rates

Abstract

Precision agriculture is a set of techniques that assist the monitoring of the agronomic performance of the maize crop by using vegetation indices. This study aimed to verify the relationship between vegetation indices, plant height, leaf N content, and grain yield of three maize varieties, grown under high and low N as topdressing. The experiment was carried out at the Fundação de Apoio à Pesquisa Agropecuária de Chapadão (Fundação Chapadão), located in the municipality of Chapadão do Sul, during the 2017/2018 season. The experiment consisted of a randomized block design with four replications, arranged in a 3x2 split-plot scheme. The first factor (plots) corresponded to three open-pollinated maize varieties (BRS 4103, BRS Gorotuba, and SCS 154), and the second factor (subplots) consisted of two N rates applied as topdressing (80 and 160 kg- 1). All the evaluated variables showed varieties x N interaction. Vegetation indices in maize varieties were influenced by the N rate applied as topdressing. Normalized Difference Vegetation Index (NDVI) and Soil-adjusted Vegetation Index (SAVI) showed a higher correlation with plant height. At the same time, Normalized Difference Red Edge (NDRE) had a stronger association with leaf N content.

SALICYLIC ACID AS A SALINE STRESS ATTENUATOR IN THE PHYSIOLOGICAL QUALITY OF Erythrina velutina SEEDS

“…The canonical variables analysis is the variation between treatments and variables, considering the residual dispersion of each variable, similar to the principal components analysis, but preferable when using an experimental design, that is, when there are repetitions in each treatment. In addition, each canonical variable is a linear combination of the variables used (Flores et al, 2020).…”

Predicting the Optimum Corn Harvest Time via the Quantity of Dry Matter Determined with Vegetation Indices Obtained from Multispectral Field Imaging

“…Furthermore, regarding the problems relevant to the topic in general, several research reports, articles, and papers discuss the relationship between the vegetation indices and nutritional values, [42,43]; the latter source examines data correlation between vegetation indices and the nitrogen nutrition index (NNI), the investigation being focused solely on pepper plants. The vegetation indices and the agronomic performance of corn varieties under different nitrogen rates are compared in article [44]. Our efforts conceptually relate especially to those outlined in report [45], which proposes an insight into the correlation between canopy vegetation and the growth indices of corn varieties with different nitrogen efficiencies; the authors of [45], however, do not show concrete mathematical expressions to inspect the vegetation-to-nutritional index relationships that allow for the establishing of the optimum corn harvest time.…”