Light and scanning electron microscopy of the Indian lotus roots invaded by Hirschmanniella diversa

Abstract

In order to clarify the parasitic behavior of Hirschmanniella diversa and host reactions in Indian lotus roots, we observed naturally infected roots from a lotus field using light and scanning electron microscopy. Light microscopy revealed that various stages such as adults, juveniles and eggs of H. diversa were present in the cortex, but none were present in the stele of the root. These results suggest that H. diversa spends a large part of the life cycle in Indian lotus roots. Scanning electron microscopy also confirmed that most H. diversa were present in the cortex cells, and revealed that in cortex cells with much smaller volumes and with lower nutrient content than the usual ones, a few H. diversa were turning with several twists of the body, suggesting these nematodes were seeking cells which could supply better feeding sites.