Table 5 Unusual morphological or developmental features among Phytophthora species

P. infestans

1

Sporangiophore apophyses

Mechanism of indeterminate sporangiophore growth

P. capsici

2

Long pedicels 30- > 100 µm

Umbellate sympodia

Splash dispersal, sporangial clustering and adherence to host surfaces

P. litchii

4

Downy white mycelium

Determinate sporangiophores and synchronous sporangial formation

Resistance to dessication on suberised fruit pericarp surface

Rapid synchronized sporulation on exposed fruit pericarp surface

P. heterospora

4

Pseudoconidia: direct germination, no papillum; formed alongside papillate zoosporic sporangia

Adaptation to both moist and drier habitats or seasonal or diurnal climate

P. pinifolia

6

Narrowing of sporangiophores near sporangial bases

Facultative caducity, enabling aerial infection and dispersal in a Clade of soil- and water-borne species

P. cinnamomi

7

Tough mycelium

Stromata

Lignitubers (intracellular hyphae encased in callose layers produced by the host cell)

Competitive growth through soil and litter

Nutrient storage for seasonal hibernation and subsequent sporulation

Long term survival

P. lateralis

8

Stromata and sporangiomata

Pressure eruption through needle cuticle followed by sporulation

P. hibernalis

8

Long pedicels 20–80 µm

Splash dispersal, sporangial clustering and adherence to host surfaces

P. ramorum

8

Stromata and sporangiomata

Pressure eruption through tough leaf cuticle or fruit periderm followed by sporulation

P. constricta

9

Sporangiophore constrictions near the sporangial bases

Facultative caducity and aerial dispersal in a Clade of soil- and waterborne species

P. insolita

9

Production of oospores without antheridia (presumed gametangial apomixis)

Inbreeding mechanism. Survival in periodically dry waterways without cost of less adapted recombinant offspring