Record ID No. |
1769 |
Author(s) |
Isobe, K., Sugimura, H., Maeshima, T., Ishii, R , 2008 |
Affiliation |
Nihon University, College of Bioresource Science, Fujisawa, Kanagawa 2528510, JAPAN |
Title |
Distribution of arbuscular mycorrhizal fungi in upland field soil of Japan - 2. Spore density of arbuscular mycorrhizal fungi and infection ratio in soybean and maize fields |
Source. Vol.(no):Page |
Plant Production Science.11(2):171-177p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Organism |
n.a. |
Country |
Japan, Asia |
Abstracts |
In this study, soil samples were collected front upland fields where maize and
soybeans had been cultivated and the density of AM (arbuscular mycorrhizal) fungal spores and the
percentage of soybean roots infected with AM fungi (infection ratio) Were assessed to determine
the factors of the soil chemical properties affecting the mycorrhizal infection. The roots and
rhizosphere soil Were sampled from 9 soybean fields and 8 maize fields in the summer of 2004. The
soil samples were examined for chemical properties (pH, electric conductivity, total phosphate,
available phosphate, and phosphate absorption coefficient) and the density of AM fungal spores.
Soybean roots were stained With trypan blue to determine the infection ratio. There Was a
significant difference in soil pH and available phosphorus content with the sampling site. The
phosphorus absorption coefficient markedly varied With the sampling site and there was a
significant difference in the phosphorus absorption coefficient with the site. The spore density
in the soybean and maize fields markedly differed with the sampling site and there Was a
significant difference spore density with the sampling site. The density of AM fungal spores in
the soybean field was negatively correlated With the available phosphorus content, and showed a
positive correlation with the phosphate adsorption. This means that an increase in the available
soil phosphorus due to the application of phosphate fertilizers Will lower the density of AM
fungal spores in the soil and that the density of AM fungi spores is generally higher in soils
With a higher phosphate absorption coefficient. It is considered that this tendency is marked in
the soil With a low phosphate adsorption coefficient. The infection ratio was positively
correlated with spore density, and negatively with the available phosphorus content. To increase
mycorrhizal infection of soybeans, we need to decrease the amount of available soil phosphorus
and simultaneously to increase the density of AM fungal spores. Excessive application of
phosphorus fertilizers should be avoided. |