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

where ink disease is rampant, disease resistant hybrids should be used in both for
plant and rootstocks.
Chestnut, preferably coming from origin regions are collected and disinfected
by soaking with fungicide. It is important to avoid problems like development
of diseases such as Sclerotinia, Phoma and Penicillium, as well as weevils of
Laspeyresia and Balaninus during storage. After soaking, seeds are slightly dried.
They can be stored in plastic bags and stratified between 0 and 4 °C. Requirements
for stratification varies with the genetic origin, between 2 and 3 months for breaking
seed dormancy (Soylu and Serdar, 2000).
Chestnuts are germinated in seeds beds using perlite, cork pine or peat as substrate.
Alternative, they can be germinated directly in containers such as wax paper
pots or plastic containers, preferably with more than 400-cm 3 capacity. If germination
is made in December in heated greenhouses, seedlings can be sold in
containers in May to June.
They can also be established in the ground. In this case, it is good practice to
prepare 30 cm-elevated beds with 1.5 m width covered with black plastic. Cutting
the main root can facilitate seedlings. Seeds are planted 20 cm apart. The black
plastic prevents weeds but it could also increase incidence of ink disease. Other
problems are birds, rabbits and rodents. Seedlings can be sold next winter.
8.2. Grafting
Chestnut cultivars have been traditionally propagated using bark graft in spring
(Figure 24) or pipe bud (Figure 17) and continue to be used in new orchards when
in situ graft is made. At present days, nurseries prepare grafted plants using different
types of grafts.
Different methods of grafting in chestnut have been published by Urquijo (1957),
Bergougnoux et al. (1978), Lagerstedt (1979), Turchetti and Gemignani (1981),
Chapa et al. (1990), Fernandez (1990), and Pereira-Lorenzo and Fernandez-Lopez
(1997a). Huang et al. (1994c) studied the grafting relationships between cultivars
of C. dentata, C. mollissima and C. crenata over seedlings from C. mollissima.
A study about five grafting methods (Chip, Cleft and Whip in spring, and Patch
and T-bud in summer) showed that summer methods are easier and more effective
since the higher temperatures causes rapid healing (Pereira-Lorenzo and Fernandez-
Lopez, 1997a). However, summer grafting is not ready for the market until the
following winter. If necessary, spring graft can produce plants for the same winter,
although they need a second year growth to get to comparable growth with those
summer-grafted plants.
8.3. Layering
Chestnut, an Ancient Crop with Future 147
It was the main way to propagate hybrids in France (Bergougnoux et al., 1978;
Breisch, 1995) and Spain (Miranda-Fontaíña and Fernandez-Lopez, 1992). Mother
plants are established to 3 × 0.5–1.5 m. They develop during four years to accumulate
starch in the collar and roots. In winter they are cut back to the ground
level. From adventitious buds, new shoots are developed the following spring. In