SOME EFFECTS OF CALCIUM DEFICIENCY ON PISUM SATIVUM

Abstract

Canada field peas were grown in nutrient solutions in which the proportion of Ca(NO3)2 was varied. Observations were recorded for external appearance and for anatomical structure. Plants starved of Ca are shorter, the lower leaves are chlorotic, and the youngest leaves are curled and tough. A comparison of the proportion of Ca used here with that used by Knop and Shive seems to indicate that several nutrient solutions in common use contain more than an optimal amount of this element. Whether the plants are grown under the usual garden conditions, in a nutrient solution containing the full quantity of Ca, or in a solution lacking Ca, the anatomical structure of the root and of the stem remains practically constant. The difference is a variation in the amount of elongation rather than in the anatomical structure as indicated by transverse sections.