1- Agriculture Organization of North Khorasan. 2014. Statistics Plant Production: Statistics garden products: Statistics acreage production and performance of the horticultural. Available at http://boe.nkj.ir/?partid=8115&item= (visited 11 June 2015).
2- Allen M. W. 1955. A review of the nematode genus Tylenchorhynchus. University of California Publications Zoology ,61: 129-165.
3- Anderson R. V. 1983. An emended description of Ditylenchus valveus Thorne & Malek, 1968 and description of D. filimus n. sp. (Nematoda: Tylenchidae) from mushroom compost in Canada. Canadian Journal of Zoology, 61: 2319-2323.
4- Anderson R. V., and Hooper D. J. 1980. Diagnostic value of vagina structure in the taxonomy of Aphelenchus Bastian, 1865 (Nematoda: Aphelenchidae) with description of A.(Anaphelenchus) isomerus n.subgen.n.sp. Canadian Journal of Zoology, 58: 924-928.
5- Atighi M. R., Pourjam E., and Okhovat M. 2011. The Genus Filenchus in Northern Khorasan Province, Iran. Iranian Journal of Plant Protection Science, 42(2): 261-266.
6- Bahmani J., Khozeini F., Barooti S., Rezaee S., and Ghaderi R. 2013. Plant Parasitic Nematodes Associated with Walnut in The Sanandej Region of West Iran. Journal of Plant Protection Research, 53(4): 404-408.
7- Bello A., and Geraert E. 1972. Redescription of eight species belonging to the super family Tylenchoidea (Nematoda: Tylenchida). Nematologica, 18: 190-200.
8- Brzeski M. W. 1983. Three new species of Ditylenchus Filipjev, 1936 and comments on Basiroides longimatricalis Kazachenko, 1975 (Nematoda :Anguinidae). Nematologica, 29: 380-389.
9- Brzeski M. W. 1991. Review of the genus Ditylenchus Filipjev, 1936 (Nematoda: Anguinidae). Revue de Nematologie, 14(1): 9-59.
10- De Grisse A. T. 1969. Redescription ou modification de quelqutes techniques utilissisedans L. etude des Nematode phytoparasutaires. Meded Rijksfaculteit der Landbouwetenschappen Gent, 351-369.
11- Filipjev I. N., and Schuurmans Stekhoven J. H. 1941. A manual of agricultural helmintology. Brill, Leiden, 878 p.
12- Ganjipour M. 2012. Identification of plant parasitic nematodes from Rhizospher of Walnut Trees in North Khorasan Province, Iran. MSc Thesis. Islamic Azad University, Science and Research Branch, Tehran.
13- Golden A. M. 1956. Taxonomy of the spiral nematodes (Rotylenchus and Helicotylenchus) and the developmental stages and host-parasite relationships of R. buxophilus n. sp. attacking boxwood. Bulletin of the Maryland Agricultural Experiment Station, A. 85: 28 p.
14- Jahanshahi-Afshar F., Pourjam E., and Kheiri A. 2005. Tylenchids associated with Jiroft orchards and description of four species new for nematode fauna of Iran. Iranian Journal of Agricultural Science, 37(3): 529-542.
15- Jenkins W. R. 1964. A rapid centrifugal flotation technique for separating nematodes from soil. Plant Disease Reporter, 48 : 692 p.
16- Mokbel A. A., Ibrahim I. K. A., and EL-Saedy M. A. M. 2006. Plant parasitic nematodes associated with some fruit trees and vegetable crops in Northern Egypt. Journal of Phytopathology, 34(2): 43-51.
17- Perry V. G., Darling M. H., and Thorne G. 1959. Anatomy, taxonomy and control of certain spiral nematodes attacking blue grass in wisconsin. Bulletin of university of wisconsin research, 207: 1-24.
18- Rafiei S., Pourjam E., and Niknam Gh. 2010. Identification of Some Nematodes Associated with Fruit Trees in Moghan Region, Iran. Journal of Plant Protection, 24(1): 69-79.
19- Raski D. J., and Geraert E. 1986. Review of the genus Filenchus Andrassy, 1954 and description of six new species (Nemata: Tylenchidae). Journal of Nematologica, 32: 265-311.
20- Shahina F. 1996. A diagnostic compendium of the genus Aphelenchoides Fischer , 1894 (Nematoda: Aphelenchida) with some new record of the group from Pakistan. Pakistan Journal of Nematology, 14(1): 1-32.
21- Sher S. A., and Allen M. W. 1953. Revision of the genus Pratylenchus (Nematoda: Tylenchidae). University of California Publications Zoology, 57: 441- 470.
22- Siddiqi M. R. 1959. Basiria graminophila, n. g. n. sp. (Nematoda: Tylenchinae) found associated with grass roots in Aligarn, India. Nematologica, 4: 217-222.
23- Siddiqi M. R. 1970. On the plant-parasitic nematode genera Merlinius gen. n. and Tylenchorhynchus Cobb and the classification of the families Dolichodoridae n. rank. Proceedings of the Helminthological Society of Washington ,37: 68-77.
24- Siddiqi M. R. 1975. Zygotylenchus guevarai. C.I.H. Description of Plant Parasitic Nematodes, Set. 5, No. 65. Farnham Royal, UK: Common Wealth Agricultural Bureaux.
25- Steel A. E. 1986. Nematode parasites of sugar beet compendium of beet diseases and insects. APS press, American Phytopathological Society St. Paul. Minnesota: 33-35.
26- Thorne G. 1941. Some nematodes of the family Tylenchidae which do not possess a valvular median esophageal bulb. The Great Basin Naturalist, Brigham Young university, Provo, Utah. 2:37-85.
27- Thorne G., and Malek R. B. 1968. Nematodes of the Northern Great Plains, Part1. Tylenchida Nemata: Secernentea. Brookins, S. Dakota, Agric. Exp. State, Bull, 31:111 p.