Identification of Ramularia Leaf Blight Cotton Disease Infection Levels by Multispectral, Multiscale UAV Imagery

Abstract

The reduction of the production cost and negative environmental impacts by pesticide application to control cotton diseases depends on the infection patterns spatialized in the farm scale. Here, we evaluate the potential of three-band multispectral imagery from a multi-rotor unmanned airborne vehicle (UAV) platform for the detection of ramularia leaf blight from different flight heights in an experimental field. Increasing infection levels indicate the progressive degradation of the spectral vegetation signal, however, they were not sufficient to differentiate disease severity levels. At resolutions of ~5 cm (100 m) and ~15 cm (300 m) up to a ground spatial resolution of ~25 cm (500 m flight height), two-scaled infection levels can be detected for the best performing algorithm of four classifiers tested, with an overall accuracy of ~79% and a kappa index of ~0.51. Despite limited classification performance, the results show the potential interest of low-cost multispectral systems to monitor ramularia blight in cotton.

Automatic Identification and Monitoring of Plant Diseases Using Unmanned Aerial Vehicles: A Review

“…Similarly, target spot and powdery mildew in soybean have been identified using a popular quadcopter, Phantom-3 (Shenzhen DJI Sciences and Technologies Ltd., Shenzhen, China) [26]. Xavier and colleagues (2019) used a multirotor UAV to identify Rumaria leaf blight disease in cotton [44]. A hexacopter, DJI Matrice 600 pro (Shenzhen DJI Sciences and Technologies Ltd., Shenzhen, China), was used to detect target spot and bacterial spot in tomato leaves [45].…”

Análise De Distorções Radiométricas De Imagens Da Câmera Tetracam Adc Lite

“…Mesmo a presença de sobras, em casos em que a altura de voo é relativamente baixa, e a resolução espacial das imagens permite resolver pixels pertencentes a esta classe espectral, não justificaria a existência de uma frequência tão grande (~10 5 pixels) de valores nulos. Esse efeito indesejável pode ser visto no histograma da imagem, mostrado na figura 2, e já foi reportado por outros autores (Huang et al, 2010;Xavier et al, 2019).…”

“…A câmera ADC Lite da fabricante Tetracam é uma versão mais leve da câmera ADC Air. Por ser mais leve, a ADC Lite tem sido amplamente utilizada em conjunto com diversos tipos de Aeronaves Remotamente Pilotadas (ARP) em aplicações diversas e, especialmente, na área de agricultura (Aguerra et al, 2011;Primicerio et al, 2012;Gehrke & Greiwe, 2013;Matese et al, 2015;Vega et al, 2015;Xavier et al, 2019).…”

Ramularia leaf spot: PCR-based methods reveal widespread distribution of Ramulariopsis pseudogycines and limited presence of R. gossypii in Brazil

“…is the world´s most cultivated ber crop, mostly for the supply of raw materials for the textile industry, as well as for oil and protein extraction 1 . Since the 1990s, Brazil has ranked globally in fourth place in terms of cotton production, following a strong investment in the production technology and in the expansion of cultivated area, mainly in the Brazilian Cerrado 2,3,4,5 (a savannah-like region in the Brazilian Midwest).…”

“…In Brazil, the disease was rst reported by the Agricultural Inspection and Defense Service of São Paulo in 1919 and was considered of secondary importance until the 90's 9,11 . Currently, RLS is the major cotton disease in Brazil, with up to eight spray applications of fungicide required to reduce its negative effects on yield and cotton ber quality 4,5,12 .…”