Abstract: Soil compaction lead to high soil bulk density negatively influences root and tuber of potato. In order to illustrate the effect and adaptation mechanisms of root tissue, stolon tissue, yield and quality of potato under different soil compaction, using potato varieties Shepody, Longshu No.8 and Qingshu No.9 as material, 0.79 MPa (T1), 0.98 MPa (T2) and 1.24 MPa (T3), on the root and stolon morphology, tuber yield and quality of potato seedlings were investigated using sand columns. The results showed that:(1) With increasing soil compaction, the root and shoot dry weight, root surface area and total root length decreased, while average root diameter and the ratio of root to shoot increased. (2) The increased soil compaction led to the increase of average stolon diameter and the decrease of stolon length. Comparing with control (T1), all the stolons length and diameter of three varieties reached significant difference at P<0.05 level. (3) Comparing with control (T1), no significant difference (P<0.05) was found in the tuber yield of three varieties under T2, whereas the significant difference (P<0.05) appeared under T3. The commodity rate of three varieties was significantly lower than control (T1) with the increasing soil compaction. (4) The dry matter and starch content were increased, the crude protein and reducing sugar content were decreased, and the vitamin C content had no significantly change with the increasing soil compaction. In this study, the response of Shepody, Longshu No.8 and Qingshu No.9 to soil compaction stress were indicated that high soil compaction was a negative impact on the growth and development of root, stolon and tuber, and also affect tuber quality.

Key words: soil compaction, potato, root, stolon, tuber yield, quality