Wirkung von Gummimehl auf Phaseolus vulgaris

Effects of ground rubber on Phaseolus vulgaris Phaseolus vulgaris was grown in sand culture containing ground rubber. The rubber caused red-brown and black spots and stripes to appear on the veins. The leaves developed widespread chlorosis. The vascular bundle tissues and the mesophyll differentiated incorrectly. Brown deposits were found in all tissues, some being manganese enriched. Plants were analysed for Boron, Cadmium, Manganese and Zinc after a vegetation period of 49 days. Zinc toxicity was considered ground rubber's primary effect. It also caused Boron starvation and excess of Manganese.