MANGANESE TOXICITY IN THREE SPECIES OF ANNUAL MEDICS

• Published in: Journal of plant nutrition 2001-12, Vol.24 (12), p.1957-1964
• Main Authors: Carneiro, João Paulo, de Varennes, Amarilis, Amante, Hugo
• Format: Article
• Language: English
• Subjects: Adaptation to environment and cultivation conditions; Agronomy. Soil science and plant productions; Biological and medical sciences; Deficiencies. Phytotoxicity of elements. Salinity; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Generalities. Genetics. Plant material; Genetic resources, diversity; Genetics and breeding of economic plants; Plant material; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Varietal selection. Specialized plant breeding, plant breeding aims
• ISSN: 0190-4167; 1532-4087
• DOI: 10.1081/PLN-100107607

The selection of Medicago spp. cultivars tolerant to high levels of manganese (Mn) is needed if they are to be established in acidic soils. We compared the growth of three species of annual medics (M. polymorpha, M. murex and M. tornata) in an acid soil with a high level of extractable Mn, and in nutrient solutions with 100 and 500 μM Mn. M. polymorpha accumulated the greatest biomass in the field, in pots, and in nutrient solution, but M. murex was the most tolerant of a high level of Mn in nutrient solution and in the unlimed acid soil in pots. M. tornata produced a similar biomass to M. murex in limed soil and in a nutrient solution with a low level of Mn. However, it was very sensitive to a high level of Mn, both in solution and in unlimed soil. The relative growth between the three species in the field, in pots, and in nutrient solution was comparable, suggesting that selection in nutrient solution can be used to identify ecotypes tolerant to Mn.