Production Practices and Quality Assessment of Food Crops. Vol. 1

146 S. Pereira-Lorenzo and A. M. Ramos-Cabrer
sitivity of C. dentata and less C. sativa to this fungus. Blight destroys the bark
and the cambium and causing the death of the branches or the tree over the wound
when the disease girdles around them (Figure 23) (Anagnostakis, 1987; Heiniger
and Rigling, 1994).
It was first observed in Europe in Genova, Italy in 1938, spreading quickly
through Italy and other European countries (Robin and Heiniger, 2002) less so in
Southern UK, Netherlands, Central and Southern Spain and the Canary Islands.
Blight almost eliminated the American chestnut (C. dentata) but European chestnut
recovered rapidly due to the natural occurrence of hypovirulence dsRNA hypovirus
CHV1. Recently, Allemann et al. (1999) have isolated five different CHV1 subtypes.
Biological control is practised in Europe applying hypovirulent strains hypovirus
to growing cankers using Grente’s method (Grente and Berthelay-Sauret, 1978).
8.1. Seedlings
8. PROPAGATION
Chestnut tree is naturally spread by seedlings, and this is the main way to produce
plants for forest plantations and traditional rootstocks. In both cases, they should
be promoted in areas over 500 m, where ink disease is less frequent. In areas
Figure 23. Chestnut blight and hypovirulent traitment.