Calcium uptake by alfalfa as modified by a mycorrhizal fungus and liming
The purpose of this experiment was to study the effect of an arbuscular mycorrhizal (AM) fungus on calcium acquisition by Medicago sativa plants grown in a medium at five levels of CaC03. Determinations of dry matter production and concentrations of N, P, K, Ca and Mg in plant tissues showed that my...
| Autores: | , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 1996 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/278132 |
| Acceso en línea: | http://hdl.handle.net/10261/278132 |
| Access Level: | acceso abierto |
| Palabra clave: | Arbuscular mycorrhiza Legume symbiosis Ca uptake |
| Sumario: | The purpose of this experiment was to study the effect of an arbuscular mycorrhizal (AM) fungus on calcium acquisition by Medicago sativa plants grown in a medium at five levels of CaC03. Determinations of dry matter production and concentrations of N, P, K, Ca and Mg in plant tissues showed that mycorrhizal colonization increased content of N, P and K and overall yield, but decreased the concentration of Ca and Mg in plant shoots. The response of mycorrhizal colonization to different amounts of extractable soil Ca indicated that, while mycorrhiza formation was not sensitive to soil Ca it induced a reduction of Ca in the plant. This study demonstrated that AM fungi modulate the ion ratios and ion balance in the plant. In general, the nutrient/Ca ratios were higher in AM than in non-AM plants. These results show that AM formation enhanced N, P and Kand decreased Ca uptake. The mycorrhizal condition affected plant tolerance to nutrient deficiency or excess by modifying uptake. Only in AM plants were differences observed between the effects of varying Ca availability. There was a positive correlation between plant Ca content and nodulation in the mycorrhizal treatments. On the other hand, nodulation was not corr.elated with N, P and K contents. Calcium amendments had no effect on nodule formation in nonmycorrhizal plants, but nodule production was highly increased in AM plants, particularly at the highest Ca level. The correlation coefficients for parameters related to absorption of nutrients in mycorrhizal plants were highly significant for N and P, as well as for Ca and nodulation. According to our results, the mycorrhizal effect on Ca assimilation was not a simple buffering effect associated with Ca excess. The impact of AM function is dependent on various soil and environmental factors. The mechanisms by which AM fungi are able to alleviate nutrient excess has yet to be understood. Further research will be necessary to elucidate this effect. |
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