Overview of Root-knot Nematode Infestation of Pistachio Orchards in Rafsanjan

In order to evaluate the root-knot nematode infestation in pistachio (Pistacia vera L.) orchards, soil and root samples of pistachio trees were collected from Rafsanjan orchards during different months of 2012-13. Based on morphological and morphometric characteristics of second larvae and adult females, M. incognita was found to be the dominant species (90% of total samples). The population dynamics of nematode larvae in the soil showed the least range 5 to 7 nematodes in June, September, December and March and the maximum, (50 to 210 nematodes per 100 grams of soil) in August. The highest density of nematodes per gram of root with 98 galls and 53 mature females were observed on August. The root-knot nematode populations were varied from 5 to 300 second juvenile per 100-gram soil. The eighteen plant species were found to be hosts for Meloidogyne incognita in pistachio orchards whereas M. javanica was observed on five species. The results of this study can determine the exact time of root-knot nematode control and the importance of weed management in pistachio orchards.