1Barbar A S, Mackay A D. Root and potassium uptake by corn genotypes in the fild[ J]. Fertilizer Res. ,1986,10:217 -231.
2Ide G Hofnan, G, Ossement C and Van Ruymbeke M. Root growth response of winter barley to subsoiling [ J ]. Soil &Tillage Research 1984,4:419 - 431.
3Rowse H R and Stone D A. Deep cultivation of a sandy clay loam; 1. Effects on growth yield and nutrient content of potatoes, broad beans, summer cabage and red beer in[J]. Soil &Tillage Research, 1980/ 1981.1:57 -58.
4Pikol J L, Aase J K. Wheat response and residual soil properties following subsoiling of a sandy loa in eastern Montana [ J ]. Soil & Tillage Research, 1999,51 ( 1 ) :61 -70.
5Browns M, Whitwell J T, Touchton J T,etal. Conservation tillage systems for cotton production [ J ]. Soil Science Society of America Journal, 1985,49 (5): 1256 - 1259.
