SHARMA, G.C.SEN, SHALINI2017-05-202017-05-202014http://krishikosh.egranth.ac.in/handle/1/5810011760ABSTRACT The present investigations were carried out duringthe period of research on “Status of plant parasitic nematodes in apple orchards of Himachal Pradesh”. In the present study, ten plant parasitic nematodes viz. T. mashhoodi, H. dihystera, P. coffeae, P. curvitatus, Meloidogyne sp., M. xenoplax, G. peperpotti. Xiphinema sp., Tylenchus sp.and H. indicus were found harboring the rhizosphere of apple orchards. Most frequently occurring nematodes were P. coffeae, H. dihystera and T. mashhoodi(100%) followed by Meloidogyne sp. (83%), P. curvitatus, Xiphinema sp. and Tylenchus sp. (33%) and M. xenoplax and H. indicus (16%). Highest population was recorded for the H.dihystera (600/ 200 cc soil) followed by P. coffeae, T. mashhoodi(500) while it remained minimum for the Xiphinema sp. (50/200 cc soil). With highest average population of 152 per 200cc soil, P. coffeae dominated the other nematodes. Among the abiotic factors recorded viz. altitude, pH, organic carbon, moisture, temperature and age of tree, altitude showed its significant positive impact on the population build up of P. coffeae i.e. with the increase in altitude the nematode population was found increased. Age of tree was also found significantly influencing the total nematode population in the orchards with its positive impact. Impact of other parameters on the population build up of nematodes remained non considerable.ennullThesis