Agriculture Reference
In-Depth Information
On the other hand, China has displayed a steady gowth in wine production since
2005 and a 3.3 fold in wine imports between 2005 and 2010, clearly indicating a
rise in demand by Chinese consumers. However, due to the very large population,
consumption per capita seemed unchanged over the same period, unlike trends in
Europe, where alcohol education has reduced wine consumption (Fig.
7.1
). Indeed,
it would only take an increase of 0.82 L per Chinese capita (just over one bottle per
person) to equal the total domestic consumtion of France (using current population
data). Clearly, in view of a rise of the Chinese middle class, China is an emerging
market with enormous potential (Fig.
7.2
).
Botany
The grapevine is a perennial species that carries out a number of integrated pro-
cesses as it progresses from dormancy through budburst, canopy development, root
growth, flowering, berry ripening, leaf senescence and then back into dormancy.
These processes include nutrient and water uptake, leaf gas exchange, and translo-
cation. Berries contain seeds, and carry out the reproductive function of the vine,
maintaining and spreading the species geographically.
Roots
The roots of a grapevine can spread over extensive distances and depths, espe-
cially in unirrigated situations. Because grapevines can live for over 100 years
the amount of biomass invested into the root system can be enormous. Older
roots are covered in a corky layer and anchor the vine in the soil. These roots also
hold a critical source of carbohydrate reserves that supports early shoot growth
shortly after budburst in spring. The fine roots, however, are covered in numerous
root hairs to increase surface area and facilitate absorption of water and minerals.
These root hairs are an extension of the epidermal cell and are very short-lived.
Soil moisture and temperature have an impact on new root growth in early spring
and this impacts nutrient and water uptake. Aside from slowing new root growth,
cool soils also hamper starch metabolism and can delay canopy and reproductive
growth such that flowering and veraison dates are delayed (Rogiers and Clarke
2013
). Because roots are in direct contact with the soil they are able to relay infor-
mation from the below-ground environment to the above ground vine components
by sending signals through the vascular system. For instance, abscisic acid is
produced in the roots in response to water deficits and sent to the leaves to initiate
stomatal closure.
