Geographical variation
There are substantial differences in wheat farming, trading, policy, sector growth, and wheat uses in different regions of the world. In the EU and Canada for instance, there is significant addition of wheat to animal feeds, but less so in the USA.
The two biggest wheat producers are China and the EU, followed currently by India, then USA. Developed countries USA, Canada, Australia, the EU and increasingly Argentina are the major exporters with developing countries being the main importers, although both India and China are close to being self-sufficient in wheat. In the rapidly developing countries of Asia, Westernization of diets associated with increasing prosperity is leading to growth in per capita demand for wheat at the expense of the other food staples.
In the past, there has been significant governmental intervention in wheat markets, such as price supports in the USA and farm payments in the EU.
In the EU these subsidies have encouraged heavy use of fertilizers inputs with resulting high crop yields. In Australia and Argentina direct government subsidies are much lower.
Farming systems
In the Punjab region of India and Pakistan, as well as North China, irrigation has been a major contributor to increased grain output. More widely over the last 40 years, a massive increase in fertilizer use together with the increased availability of semi-dwarf varieties in developing countries, has greatly increased yields per hectare. In developing countries, use of (mainly nitrogenous) fertilizer increased 25-fold in this period.
However, farming systems rely on much more than fertilizer and breeding to improve productivity. A good illustration of this is Australian wheat growing in the southern winter cropping zone, where, despite low rainfall (300 mm), wheat cropping is successful even with relatively little use of nitrogenous fertilizer. This is achieved by ‘rotation cropping’ (traditionally called the ley system) with leguminous pastures and, in the last decade, including a canola crop in the rotations has boosted wheat yields by a further 25% .
In these low rainfall areas, better use of available soil-water (and better control of soil erosion) is achieved by retaining the stubble after harvesting and by minimizing tillage.
