EFFECT OF SOIL STRENGTH ON ROOTS AND VEGETATIVE GROWTH OF WHEAT AT SEEDLING STAGE

The effect of soil strength (SS) on the performance of three UK wheat genotypes i.e., Rht or Rht1 or Rht3 was studied. These genotypes were all basically the variety Mercia but containing stem dwarfing genes referred to as Rht or Rht1 or Rht3. Experiment was conducted in a controlled environment growth cabinet at Rothamsted. For the measurements of leaf area and the number of tillers per plant there was no significant genotype x SS interaction. But the Rht1 showed the greatest relative decline in the strong soil. However shoot and root weight, root number, the maximum depth of rooting all showed some genotype x SS interaction. In all cases it was only the Rht1 that showed statistically significant (p>0.05) difference between the two SSs. It is concluded that the stem dwarfing genes in Rht and Rht3 may have the potential to give the advantage of high productivity associated with dwarf plants, without the penalty of weaker root systems. They may therefore be useful in breeding programmes to develop wheat varieties suitable for soils with high strength.