DROUGHT TOLERANCE IN POTATOES

In field experiments made over 3 years Pentland Crown and Majestic gave, in general, higher total and dry matter yields from plots given no supplementary water and protected from rainfall throughout growth than King Edward or Maris Piper. However, on plots kept at or near to field capacity all varieties gave similar yields. Pentland Crown and Majestic were deeper rooting than the other two varieties at the time of tuber formation (when the production of new roots ceased) but the differences in rooting depth (co. 100 mm) between the varieties were small. Except for the top 150 mm of soil, differences in water extraction between the varieties throughout the profile were also small. Neither these differences in water extraction nor the differences in rooting depth could be related consistently to the differences in varietal yield response between ‘wet’ and ‘dry’ plots. © 1979, Cambridge University Press. All rights reserved.