塩ストレス条件下におけるAsteriscus maritimusの生長に対するアーバスキュラー菌根共生の影響

抄録

Increased salinization of arable land is anticipated to raise devastating global effects in the coming years. Mediterranean countries already have both arable land salinization and desertification problems. Arbuscular mycorrhizal (AM) fungi have been shown to improve plant tolerance to abiotic environmental factors such as salinity. The AM fungi Glomus coronatum, which is a reperesentative species in salinity environments, and isolated from sand dunes in the Natural Park of Cabo de Gata (SE Spain) was used in our study. Two other AM fungi isolated from non-salinized environments; G. intraradices and G. mosseae were also used in the experiment. Asteriscus maritimus (L.), a member of the Asteracea family, was selected to carry out the greenhouse experiment to be native of lands surrounding the Mediterranean Sea, especially Spain. In this study, A. maritimus plants were grown in sand and soil mixture with two NaCl levels (0 and 50 mM) during 10 weeks of non-saline pre-treatment, following 2 weeks of saline treatment. Results showed that inoculated plants grew more than nonmycorrhizal plants. Unexpectedly G. intraradices was the most efficient AM fungi in terms of fresh weight, dry weight and Qyield although plants inoculated with G. coronatum showed better stomatic conductance. Plants inoculated with G. mosseae showed a intermediate pattern between the other two AM fungi. Based on these results, the AM fungi inoculation helps the growth of A. maritimus in saline conditions and G. intraradices appears to be the most efficient of the three AM fungi studied. This study may be useful in revegetation and regeneration projects by selecting adequate species of AM fungi.