Rothamsted Symposium on Trace Elements 



66 



The variety "Dubbele Prinsesseboon" was chiefly studied in 

 1946. Samples were taken on June 27, when symptoms on the 

 young plants were severe, and on July 12, when recovery had set 



pp.in 

 5200 



15 10 



pH VS iCO tit 3.8 



Textfigure 8.— Manganese content of foli- 

 age of Phaseolus vulgaris (Dubbele Prinsesse- 

 boon) grown on plots with various amounts of 

 limestone (1947). 



in on the less acid plots. Plants sometimes recovered to such an 

 extent that mainly the oldest leaves continued to show injury. 

 The results of the chemical analysis are summarized in Figure 7. 



