Postprint version. Published in Developments in Plant and Soil Sciences, Volume 54, January 1, 1993, pages 747-750.
Copyright © 1993 Springer. The original publication is available at http://www.springer.com/life+sciences/plant+sciences/book/978-0-7923-2540-6.
NOTE: At the time of publication, the author G.S.P. Ritchie was not yet affiliated with Cal Poly.
A pot experiment was conducted to establish whether gypsum or lime could increase wheat growth in an acid subsoil. Wheat (Triticum aestivum c. v. Gutha) was grown in 3 kg of soil which had been mixed with basal nutrients and different rates of gypsum and lime. Wheat in the treatment which received no gypsum or lime showed the most severe nutrient deficiency symptoms and had the lowest shoot and root dry weights. Lime treatments increased shoot and root growth 2 to 3 fold and decreased the concentration of total Al and the calculated activities of all Al species. Gypsum increased shoot dry weight to up to 50% but decreased root dry weight and root length compared with unamended soil; it had little effect on the pH and concentration of total Al in the soil solution but decreased the sum of the activity of monomeric Al ions and increased the activity of the AlSO; ion pair. Both gypsum and lime increased uptake of Ca, Mg, S, P and K in plant shoots. It is suggested that lime increased plant growth by increasing the pH and markedly decreasing the concentration of Al in the soil solution, enabling plants to take up other nutrients from the soil. It is further suggested that gypsum decreased the activity of toxic monomeric Al species and therefore enabled better nutrient uptake. The results indicate that subsurface incorporation of lime would be the best method for improving wheat growth on yellow sandplain soils in Western Australia if an economic method for incorporation of lime into the subsoil could be developed.
Food Science | Nutrition