Dartmouth Electron Microscope Facility Date: Tue 25-Oct-2011 Time: 10:56
01 PSpy4_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing bacteria and fungi on lower leaf surface.
02 PSpy5_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing bacteria and fungi on lower leaf surface.
03 Cort4_Aug2011-3.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing fungal hyphae on lower leaf surface.
04 Cort6_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard
Rosales
Rosaceae
Malus domestica
Fungal spores bursting through a lesion on the leaf surface, might be Venturia inaequalis conidia (conidia are fungal spores produced asexually by various fungi at the tips of specialized hyphae).
The apple scab infection cycle starts with the release of V. inaequalis ascospores from leaf litter around the tree. The spores rise into the air and land on the surface of a susceptible tree, where they germinate and form a germ tube that can penetrate the plant's waxy cuticle. A fungal mycelium forms, grows, and then ruptures into a black lesion. From this lesion,  conidia are released and germinate on fresh areas of the host tree, which in turn produce another generation of conidial spores. This cycle of secondary infections continues throughout the summer.
05 Cort6_Aug2011-2.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing fungal hyphae on lower leaf surface.
06 Cort6_Aug2011-3.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

High magnification image of Cort6_Aug2011-2
07 Cort7_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing fungi on lower leaf surface.
08 Cort5_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image, showing fungi and fungal spores on lower leaf surface.
09 Cort7_Aug2011-6.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image of stomate on lower leaf surface, with fungi and fungal spores present.
10 PSpy5_Aug2011-1.jpg IInstrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image of lower leaf surface, with fungi and bacteria around the stomate.
11 PSpy5_Aug2011-2.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image of lower leaf surface.
12 PSpy5_Aug2011-3.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image of lower leaf surface, with bacteria and fungi.

13 PSpy6_Aug2011-1.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica

Scanning electron microscope image of lower leaf surface, with fungal hyphae and a spore visible in lower right quadrant of image.
14 PSpy6_Aug2011-2.jpg Instrument: FEI XL-30 FEG ESEM
Microscopist: Louisa Howard

Rosales
Rosaceae
Malus domestica


Scanning electron microscope image of lower leaf surface, with fungal spore and hyphae.

Dartmouth Electron Microscope Facility