Effects of mycorrhizal inoculation on tomato growth and arsenic absorption under arsenic (As) contamination

Tomato plants growing in soils with different concentrations of arsenic were inoculated with mycorrhizal fungi to study the effects of mycorrhizal fungi on tomato plant growth and the arsenic absorption under arsenic (As) contamination conditions. The results showed that the total root length and specific root length ratio decreased with the increase of soil arsenic concentration，and soil arsenic contamination significantly increased the arsenic concentration of whole tomato plants（including aboveground parts and roots）. When the soil arsenic concentration increased from 0 mg/kg to 100 mg/kg，the root shoot ratio of tomato plant increased during the seedling stage，and the fruit ratio and fruit quality dropped in the fruiting stage; however，mycorrhizal fungi inoculation during the anthesis stage and fruiting stage，could significantly decrease the root shoot ratio，and promote the quantity and quality of fruits. Mycorrhizal fungi inoculation reduced fruit arsenic absorption and content of tomato plants growing in the arsenic contaminated soil. When the soil arsenic concentration attained to 200 mg/kg，the root shoot ratio of un-inoculated plants increased evidently during the anthesis stage and fruiting stage; neither the inoculated nor un-inoculated plants would fruit.