Leaf nutrients(N,P,K,Ca and Mg) in selected Populus tomentosa triploid clones

Concentrations of nutrients(N,P,K,Ca,and Mg) in leaves of triploid Populus tomentosa were studied with 12 treatments(11 triploid clones:S1, S2, S3,S4,S5,S6,S7,S8,S9,S11,S12)and a duple clone(S10) as a control.The results showed that compared to the control,concentrations of N in clones S11,S1,S6,S3,S7,S8 and S4 were significantly greater(P0.05,n=36),concentrations of K in all triploid clones were significantly greater(P0.01),concentrations of Ca in all triploid clones were significantly less(P0.01),and concentrations of P and Mg were not significantly different.N concentrations excluding the control ranged from 24.56 g·kg-1(S11) to 21.23 g·kg-1(S9);P concentrations from 1.81 g·kg-1(S5) to 1.24 g·kg-1(S2);K concentrations ranged from 19.46 g·kg-1(S4) to 15.20 g·kg-1(S10);and Ca concentrations ranged from 11.35 g·kg-1(S10) to 5.93 g·kg-1(S8).Nutrient concentrations in leaves of triploid P.tomentosa were in the following order: N K Ca Mg P.[Ch,5 fig.1 tab.15 ref.]