Observations are based on original research. A background information is given about plant parasitic nematodes and the observations made on the infected root of apple tree are reported. A total of 220 samples of apple tree roots of 10 different localities of Kalat district, Balochistan, were collected. Apple roots were found infected with nematodes belonging to the genera, Aphelenchus, Boleodorus, Helicotylenchus, Merlinius, Pratylenchus, Psilenchus and root knot nematode Meloidogyne. Root tissue damage caused by root knot nematode was studied and repoted. Study of histology sections revealed...

Tissue damage in the liver and intestine of viper snake by nematodes and in the intestine of cobra by an acanthocephala is described here. These snakes were naturally infected with the parasites. Study of tissue sections revealed that the nematodes in the liver of viper cause severe damage including destruction of general architecture, atrophy and fibrosis. Lobular configuration of liver was disturbed, coagulated necrosis has occurred, melanomacrophage centers appeared. Bile duct hyperplasia with marked colangiohepatitis was observed. In the intestine the nematode caused fusion and...

Tissue damage in the naturally infected intestine of the popular edible fish Parastromateus niger by the acanthocephalan parasite Serrasentis niger Bilqees, 1972 is described here based on original research. This infection caused considerable tissue damage. Penetration of the spiny proboscis of the parasite resulted into perforation of intestine wall and severe tissue reactions. Microscopic examination of the histology sections of infected intestine revealed destruction of all layers of intestinal wall. Degeneration of mucosa with necrosis was a common finding. Intestinal mucosa was...