Baking Quality of Wheat (Triticum aestivum) Grown Intercropped with Leguminous Crops

Summary in the original language of the document

In order to find out if intercropping wheat with faba bean and/or lupin can be a way to improve baking quality of wheat, trials have been conducted. Many wheat varieties have been tested in monoculture and with several faba bean and white lupin varieties. Four indicators for baking wheat quality are assessed: protein content, Zeleny sedimentation value, falling number and hectolitre weight. These are used in order to set the wheat price by the Dutch grain collector Agrifirm. The protein content is connected to water absorption of the wheat flour and extensibility of the dough. The Zeleny sedimentation value quantifies the amount of gluten-forming proteins, which are important in bread production as they facilitate extensibility of the dough which causes the dough to rise in the oven, and the elasticity of the dough. The falling number is a measure for the conversion of starch into sugars caused by premature germination. An excess of sugar causes unwanted stickiness of the dough. A high conversion of starch into sugars is demonstrated by a low falling number. The last indicator that will be discussed is the hectolitre weight, which is an indicator for the flour yield from the wheat seeds.
The results show that a lower wheat planting density is beneficial for the protein content (p<.05) and it also seems to have a positive effect on the Zeleny sedimentation value, both in monoculture and in intercrop with faba bean. Intercropping wheat with faba bean and lupin both showed an increase in protein content and Zeleny value, compared to wheat that is grown in monoculture. The falling number is not much affected by intercropping, however, it was already of sufficient level according to the wheat rewarding system of Agrifirm. The results from the intercropping trials are very promising for the wheat production in the Netherlands. The challenge is to fine-tune combinations of wheat and legume, and to find out in which combination the effect is sufficient and stable.