Abstract
Pigweeds (Amaranthus species), negatively impact crop production systems throughout the world. They are distinguished from each other using manual methods that are tedious and time-consuming to complete. Hyperspectral light reflectance properties of plant leaves and canopies have shown promise for detecting and mapping weeds in crop production systems. Vegetation indices derived from hyperspectral reflectance data enhance differences between plants, leading to better detection of them from other targets. The objective was to evaluate the biomass and structural index, the biochemical index, the red edge index, the water and moisture index, the light-use efficiency index, and the lignin cellulose index for measuring differences among six pigweed species: Amaranthus albus (L), A. hybridus (L), A. palmeri (S. Wats.), A. retroflexus (L), A. spinosus (L), and A. tuberculatus [(Moq.) Sauer]. Two experiments were conducted under greenhouse conditions. Hyperspectral reflectance measurements were collected from the plant canopies on two dates for each experiment. Analysis of variance (ANOVA) and Tukey’s honest significant difference (HSD) test were used to determine if statistical differences (P ≤ 0.05) existed among the pigweed species canopies and to identify which species were statistically different for a vegetation index, respectively. The ANOVA analysis detected statistical differences among the canopy vegetation index values. Tukey’s HSD showed that the biochemical index and the red edge index detected differences between two to three pigweeds species on all dates of data collection. However, the differences were date-specific. Furthermore, statistical differences were not observed for all six species for any vegetation index. On the data collection dates, A. albus and A. tuberculatus index values were statistically different from other pigweed species for one or more of the vegetation indices. Future research should focus on using the vegetation indices in combination with each other to measure differences between the pigweed species and between them and other weeds and crops.
Highlights
Pigweeds (Amaranthus spp.) negatively impact crop production systems in the United States and throughout the world [1] [2] [3] [4] [5]
Analysis of variance (ANOVA) and Tukey’s honest significant difference (HSD) test were used to determine if statistical differences (P ≤ 0.05) existed among the pigweed species canopies and to identify which species were statistically different for a vegetation index, respectively
On December 4, 2019, A. hybridus was separable from A. spinosus and A. albus with the biochemical index; A. tuberculatus was distinguishable from A. palmeri with the red edge index
Summary
Pigweeds (Amaranthus spp.) negatively impact crop production systems in the United States and throughout the world [1] [2] [3] [4] [5]. Pigweeds serve as host plants for crop pests, including insects, viruses, and fungi [7] [8]. Their pollen can cause an allergic reaction to sensitive individuals [9] [10]. Pigweeds known to cause problems in agriculture are Amaranthus albus, A. blitoides, A. hybridus, A. palmeri, A. powelli, A. retroflexus, A. spinosus, and A. tuberculatus [5] [6]. They have developed resistance to herbicides used in crop production systems [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
