Evaluation of wavelet spectral features in pathological detection and discrimination of yellow rust and powdery mildew in winter wheat with hyperspectral reflectance data
Key weather factors determining the occurrence and severity of powdery mildew and yellow rust epidemics on winter wheat were identified. Empirical models were formulated to qualitatively predict a damaging epidemic (>5% severity) and quantitatively predict the disease severity given a damaging epidemic occurred. The disease data used was from field experiments at 12 locations in the UK covering the period from 1994 to 2002 with matching data from weather stations within a 5 km range. Wind in December to February was the most influential factor for a damaging epidemic of powdery mildew. Disease severity was best identified by a model with temperature, humidity, and rain in April to June. For yellow rust, the temperature in February to June was the most influential factor for a damaging epidemic as well as for disease severity. The qualitative models identified favorable circumstances for damaging epidemics, but damaging epidemics did not always occur in such circumstances, probably due to other factors such as the availability of initial inoculum and cultivar resistance.
The article presents materials on the influence of calculated doses of mineral fertilizers on the incidence of powdery mildew, pyrenophorosis and yield of winter wheat varieties cultivated on leached Chernozem for 2016-2018.
In the article the research the results of studies of the phytosanitary state of winter wheat sowing with three soil treatments - plowing (22-24 cm), shallow (10-12 cm) and zero (no - till) with various doses of fertilizers: N56 Р16 К16 , N110-130 Р90 К110 and N145-165 Р135 К150 , without fertilizers (control) for the two predecessors - soybean and rapeseed.
The influence of these methods on the development and prevalence of powdery mildew, septoriosis of leaves, root rot of winter wheat, the most common pests in the area of research - cereal flies, wheat thrips and grain sawflies. The identified measures to limit the development and spread of harmful organisms above.
Detection of Powdery Mildew in Two Winter Wheat Plant Densities and Prediction of Grain Yield Using Canopy Hyperspectral Reflectance