| Abstract: | Lodgepole pine seedlings were grown in solution culture withtheir root systems divided between two contrasting nutrientregimes, viz. a high regime, which provided near optimum conditionsfor growth, and a low regime in which nutrients were limiting.The high nutrient regime stimulated root growth whereas theroots receiving a low level of nutrients grew comparativelyslowly and in certain instances stopped elongating and becamebrown. After differential root growth had been induced certainplants were transferred to a uniform high nutrient environmentand the previously deprived parts of the root system respondedby renewed growth and their growth rate increased in comparisonwith roots which remained in low nutrient conditions. The results show that initial nutritional differences in theenvironment do not lead to dominance in certain roots; the rootsystem remains remarkably plastic. |
