Life cycle, histopathology and yield loss caused by root knot nematode, Meloidogyne incognita on noni.

摘要

Noni is considered a panacea to cure many diseases as a health supplement or as a therapy. It is gaining popularity for its use as an alternative herbal medicine. Root knot nematode, Meloidogyne incognita is one of the most destructive pathogens of noni. Due to its obligate and endoparasitic nature, it disrupts the physiology, arrests the growth of plants and reduces fruit yield and quality which ultimately results in great economic loss. Yield loss caused by root knot nematode in noni was found to be 42.8 and 46.6 per cent in two experiments conducted simultaneously at different locations. Histopathological studies of the infected root revealed severe dislocation of xylem and phloem vessels in the cortical region and in addition it was observed that egg masses were laid inside the root rather than outside and this significantly manifested the severity of the disease.