Mn use efficiency in different wheat cultivars

Mn plays an important role in plants. Soil Mn deficiency may markedly limit production of cereals, such as wheat. Wheat crop Mn deficiency can be corrected by application of Mn fertilizer, however, growing wheat cultivars adapted to Mn-deficient soils would represent a long-term solution and sustainable approach to wheat agronomy. The aim of this research was to characterise the physiological basis in Mn efficiency identified among a range of UK wheat cultivars grown in Mn-deficient soil in pot trials. Results demonstrated that the old spring wheat cultivar Maris Butler is Mn-efficient when grown in Mn-deficient conditions in comparison with modem commercial cultivar Paragon. Plants of cv. Maris Butler grown in Mn-deficient soil showed a mean relative dry matter 80% of plants in Mn-sufficient soil, whereas the modem cultivar Paragon gave a relative value of 55%. The Mn efficiency in cv. Maris Butler was shown to be related to an improved internal utilization of Mn, rather than to a higher plant Mn accumulation, which was expressed as an improved efficiency of photosynthetic photosystem II. From this study, it is suggested that cv. Maris Butler could be further examined as a potential genetic resource in future wheat micronutrient efficiency improvement programs aimed at achieving Mn efficiency in wheat. It is also suggested from this study that more than one mechanism has arisen in wheat to confer tolerance to Mn deficiency. (c) 2005 Elsevier B.V. All rights reserved.