Wheat Roots and Yields - Dr Richard Whalley, Rothamsted Research скачать в хорошем качестве

Wheat Roots and Yields - Dr Richard Whalley, Rothamsted Research

In this seminar the effects of soil structure on rooting depth in wheat are discussed. It is argued that deep rooting in wheat is the result of the interaction between soil structure and root architecture. An attempt to use laboratory root screens to predict rooting depth in the field is described. Although lab screens show genotypic differences in the architecture of seedling roots, these are not reflected in differences in rooting patterns in the field. Wheat lines with deep roots are high yielding, but it is not essential to have deep roots for high yields in the UK environment. The deepest rooting wheat lines were amongst those with the greatest number of shallow roots. In the second part of this seminar the impact of root impedance on shoot growth is described. Strong surface layers are correlated with lower yields irrespective of whether they are strong due to drying or compaction. Even relatively wet soil can have a high impedance to root elongation. In laboratory experiments root impedance stunts leaf elongation, irrespective of water and nutrient supply. Wheat with the tall Rht allele are most sensitive to the effects of root impedance on shoot growth.