Sampling grids for monitoring Euschistus heros infestation in soybean
ABSTRACT Euschistus heros is one the most important pest insect in soybean fields in Brazil. Therefore, site-specific management applied for controlling E. heros can result in economic and environmental benefits. However, sampling protocols for assessing spatialtemporal variability of this soybean pest and, then, for guiding a more sustainable pest management, were still unknown. Thus, the objective of this study was to compare the efficiency of sampling grid sizes for monitoring the spatial variability of E. heros infestation along the soybean reproductive stages. Nine sampling campaigns were carried out using the beating sheet method, from R2 to R7 soybean phenological stages. It was used a sampling grid of 10 × 10 m, totaling 338 points in an soybean field of 3.4 ha, located in Londrina, PR, Brazil, during the 2011/2012 growing season. Increased sampling grid sizes (i.e., 10 × 10 m, 10 × 20 m, 20 × 20 m, 20 × 30 m, 30 × 30 m, 30 × 40 m, and 40 × 40 m) were simulated by deleting points from the initial (reference) sampling grid. The data were analysed through statistical and geostatistical procedures. Thematic maps were built and compared using Pearson’s correlation and relative deviation coefficient (RDC). Spatial variability distribution pattern of E. heros infestation was dependent on sampling grid size and infestation pressure, in which smaller sampling grids and higher E. heros infestations enabled a more accurate monitoring. Based on study, an accurate protocol (r > 0.70 and RDC < 20%) for monitoring high infestation (i.e., > 2 individual per meter) of E. heros in soybean reproductive stages should include sampling grids smaller or equal to 20 × 20 m.
| Auteurs principaux: | , , , , , |
|---|---|
| Format: | Digital revista |
| Langue: | English |
| Publié: |
Instituto Agronômico de Campinas
2017
|
| Accès en ligne: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052017000300386 |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|