Plant Nematology: Cyst and Root Knot Nematodes

Recently, there has been a glut in the publication of so many books in plant nematology providing up to date information but the knowledge on various aspects of nematode study is so fast appearing in literature that it is becoming difficult to put that into black and white in one publication. The group is so large (an astronomical number of individuals, representing perhaps four out of every five multicellular animals on earth) and so ecologically, morphologically, and phylogenetically diverse that to attempt to discuss the diversity of the group in such a comprehensive way is practically futile. Efforts are being made to look for more fossil records to know exact time of their appearance in the universe. From the known fossil observations, their age is estimated to be 28000 years old. However, through application of various models of molecular evolution and molecular clock theory, estimates of the time of divergence of the nematodes from the rest of the animal groups appears to be about 1,177 ± 79 million years.