Winter wheat in Europe

Abstract

Directly transposing a specific wheat-growing system or blueprint for a high-yielding crop from one country to another is not possible because of differences in climatic factors and soil types between wheat-growing areas of the world. This is especially so between New Zealand and the United Kingdom and other European countries, although certain parts of the different systems are applicable to New Zealand and some are already being practised. Ninety per cent of the wheat grown in the United Kingdom is winter wheat, and is in the ground for 10-11 months of the year. Establishing plants early and having a well-grown crop before winter is desirable, especially on lighter sandy soils which may run into moisture stress during later stages of growth. In New Zealand, because of the different varieties here, having wheat in the ground for 10-11 months of the year is not necessary, but autumn-sown crops should still be well established before winter; early May-sown rather than June-sown crops. U.K. farmers like to see 250-300 plants a square metre established upon which they can build a high-yielding crop. Head populations are still about 500 heads a square metre at harvest. The common theme of all high-yielding crops in both United Kingdom and Europe is these produce about 20,000 grains/m2. A 1000 seed weight of 50 grams would result in a 10 tonnes to a hectare crop. A high-yielding wheat crop removes 20-25 kg of nitrogen a tonne of grain produced, so an eight tonne/ha crop must have access to 160-200 kg N/ha during growth, especially during rapid growth of GS 5 to GS 10.5. In good fertility this could be supplied from the soil. but in continuous cereal cropping must all be applied from the bag. In the U.K. in an average-yielding situation this would be all applied at GS 5, but where high yields were expected (8-11 t/ha). especially where high rates of nitrogen are used (200 kg N/ha), a small amount (40-50 kg N/ha) would be applied during tillering and the rest at GS 5. When working out the amount of nitrogen to be applied to a crop, various prediction methods, including soil tests, are available, but a key factor should be the potential yield of the crop. In New Zealand the yield potential should be set for different areas and different soil types. Another important factor in attaining high yields in U.K. and Europe is disease control. Not all farmers are insurance spraying, although some do. Others are looking for economic yield responses from spray programs. In general, these farmers are following the ADAS threshold levels for timing disease sprays. Threshold levels for different diseases should be set for New Zealand conditions, so farmers will know at what levels controlling different diseases is economic. This approach also involves regular crop inspection for disease levels in all crops and whether these are building up or declining. Nearly all the wheat crops in the U.K. and Europe are tramlined, allowing entry of a specially-equipped vehicle to travel through the crop with fertiliser, herbicide, fungicide or insecticide, without causing damage. In New Zealand this approach could be used on crops with high-yield potential, especially when fungicide may have to be applied at a late stage of growth. As costs were increasing faster than the price of wheat. U.K. and European farmers were becoming very cost conscious and looking for economic yield increases from all crops. This required a more positive approach to monitoring crop growth, especially for disease control, rather than just carrying out routine or insurance monitoring. Farmers were often using lower levels of inputs, particularly pesticides, to give greater growth margins.