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

vineyards and north facing to chestnut orchards. Early-frost in autumn can also
reduce the harvest in late bearing cultivars frozen the nuts in the bur after 1st
November.
Minimum rainfall for chestnut is 800 mm, so in Spain this is ideal in rainy
areas like Galicia (North-western Spain), which has 2000 mm rainfall (Pereira-
Lorenzo and Ramos-Cabrer, 2002).
Main limitation for nut production is low temperatures, which enables the female
flowers to be fecundated and to develop a normal kernel as was described by Breisch
(1995).
Chestnut trees do not thrive in soil rich in active Calcium, basic pH and poor
drainage. Therefore it is grown in sandy, poor soil to loamy soil on slopes. It is
also found grown in volcanic islands like Sicily, Canary Islands, Madeira and Azores.
Gallardo-Lancho (2001) reported the ecological conditions of Spanish chestnut
coppices to include fine earth fraction with means varies between 41% to 58%,
sand between 26% and 60%, silt between 28% and 47%, and clay between 12 and
31%. The pH (H 2O) ranged from 4.6 to 5.2.
3. BIOLOGY
Genus Castanea (2n = 24) belongs to the Family Fagaceae, so as other timber
production genera like Fagus and Quercus (Castroviejo et al., 1990). Genus Castanea
includes 12 species (Dode, 1908 and Camus, 1929, cited by Fenaroli, 1945):
Castanea sativa Miller, C. crenata Sieb. e Zucc., C. mollissima Blume, C. seguinii
Dode, C. davidii Dode, C. henryi Rehder e Wilson, C. dentata Borkhausen, C. pumila
Miller, C. ashei Sudworth, C. floridana Ashe, C. alnifolia Nuttal y C. paucispina
Ashe.
Three of the most important crop species are C. sativa in Europe, and C.
mollissima and C. crenata in Asia. C. sativa is also used for timber production,
so is the American species C. dentata, a nearly extinct species threaten by blight
during 20th century.
Interspecific hybrids were created from C. sativa with C. crenata or C. mollissima
in Europe (Urquijo, 1957; Bruneton, 1984; Fernandez et al., 1995). Selected
by their resistance to ink disease (Phytophthora spp.) and used in new plantations
as rootstocks, for production of fruit, timber or both (Breisch, 1995; Pereira-Lorenzo
and Fernandez-Lopez, 2001). In United States C. dentata was crossed by C. crenata
and C. mollissima to introduce resistance to blight (Chryphonectria parasitica)
(Anagnostakis, 1992).
3.1. Morphological description
Chestnut, an Ancient Crop with Future 111
Comparative description between main species can be found in Camus (1929) and
revised by Bourgeois (1992) (Table 4). Height of the trees and morphology of the
shoots, leaves and fruits are the most informative characteristics. The most vigorous
species are C. sativa and C. dentata, and they are used for timber production. The
angular shoots of European chestnut differentiate it from Asiatic ones, while the