TESIS DOCTORAL - RiuNet - Universidad Politécnica de Valencia

Chapter 1
A B
C D E
F G H I
Figure 1.2. A, Conidiophores of Ilyonectria liriodendri; B, Macro- and microconidia of I. liriodendri; C,
Chlamydospores in chains of “Cylindrocarpon” pauciseptatum; D, Conidiophores of Campylocarpon
fasciculare (Halleen et al., 2004); E, Macroconidia of Campyl. fasciculare (Halleen et al., 2004); F,
Penicillate conidiophores of Cylindrocladiella parva; G, Terminal vesicles of Cyl. parva; H, Conidia of
Cyl. parva; H, Chlamydospores in chains of Cyl. parva. Scale bars: a-c, f-i = 10 µm; d = 50 µm; e = 30
µm.
In this sense, Halleen et al. (2003), concluded that black-foot pathogens from
soils infected grafted grapevines once planted in open-rooted nurseries, whereas these
pathogens rarely occurred in rootstock propagation material prior to planting. During
the grapevine propagation process, at the time of planting, the susceptible basal ends
(especially the pith area) of most of the nursery cuttings are partly or even fully
exposed, and the young callus roots also break during the planting process, resulting in
small wounds susceptible to infection by soilborne pathogens. Thus, the occurrence of
black-foot pathogens in the graft union might be explained by the nursery practice of
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