The larger round structures are hazelnut pollen grains while the elongate blue structures are asci with 8 spores of Anisogramma anomola (a fungus that causes Eastern Filbert Blight).
Botrytis isolates growing on a Petri plate with fungicide amended media. Fungicide is more concentrated toward the center of the plate. S = susceptible reaction where the colony is wider as the fungicide concentration decreases to the outside. R = resistant reaction where the colony is wide from low to high fungicide concentrations.
Plant Growth Regulation (PGR) effect on rose due to application of a DMI or group 3 fungicide. This is also referred to as the "draw string" effect due to the puckering of the leaf.
Pesticide storage facility.
In this section
Leaf spots due to fluorine toxicity.
Nitrogen deficiency on this rododendron. Note that the chlorotic leaves are the lower older leaves.
Potassium deficiency in snap beans. Note the brown necrotic margin of many leaves.
Bitter pit of apple due to calcium deficiency which can occur for many reasons such as fast growth.
A common cause of tree damage in backyards and small woodlands is from sapsuckers (Sphyrapicus spp.), which are a species of woodpecker.
Sapsucker holes, approximately 0.25 inch in diameter, in horizontal and vertical rows.
Thin-barked trees such as birch are particularly susceptible to sapsucker damage.
