Effect of Liming on Potato Yields as Related to Soil pH, Al, Mn, and Ca
1982
van Lierop, W. | Tran, T. S. | Banville, G. | Morissette, S.
The objective of this study was to select the most dependable soiltest criterion for determining whether potato (Solanum tuberosum L.) yields might be increased by liming soils. To achieve this end, the crop was grown in unlimed and limed treatments of eight coarsetextured soils (Spodosols), with initial pH values ranging from 4.62 to 5.02 (H₂O) and 4.32 to 4.76 (0.01 M CaCl₂), in a greenhouse experiment. Liming at 8 g CaCO₃/8 liter soil (≃ 2,000 kg/ha) increased the average tuber yield of three soils by 40%. No yield increases were, however, produced by liming soils which had pH values higher than 4.6 (0.01 M CaCl₂) or 4.9 (H₂O). Extractable soil Al (I N KCl) was as good an indicator as soil pH for predicting crop response to liming. Yields were generally not increased by liming when the concentration of extractable soil Al was < 0.90 meq/100 g. Manganese concentrations in soil or plants were not reliable indicators for predicting the response of this crop to liming. A relationship was found between the concentration of soil Mn extracted with either 1 N NH₄OAc or 1 N KCl and the concentration of this element in plant tops (r ≃ 0.75**, significant at the 0.01 level); furthermore, the concentrations of Mn extracted by these solutions were related (r = 0.92**. The Mn content in plant tops also tended to decrease exponentially as soil pH increased (R² = 47%). Finally, no Ca-deficiencies were observed on these soils; apparently this crop can absorb sufficient Ca when soils contain as little as about 0.7 meq Ca/100 g (140 µg/g).
显示更多 [+] 显示较少 [-]