1154

Specialia

l o c a t i o n f r o m t h e r o o t t o t h e s h o o t a. The effects of Mn on t h e a b s o r p t i o n of some m o n o v a l e n t cations were investig a t e d 4, a n d it was f o u n d t h a t Mn i n h i b i t e d t h e u p t a k e of N a f r o m 0.1 m M NaC1 a n d t h a t of K f r o m 5 m M KC1. Mn also r e d u c e d t h e a b s o r p t i o n of Ca a n d Zn ~. I n c o n t r a s t , t h e p r e s e n t s t u d y reveals t h a t t h e effect of Mn on t h e a b s o r p t i o n of F e is d i f f e r e n t f r o m t h o s e on o t h e r cations r e p o r t e d earlier 4, 5.

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