Rawat, ShilpiManisha Dev2021-09-152021-09-152021-08https://krishikosh.egranth.ac.in/handle/1/5810175776Medicinal plants are gaining importance globally because of their multifarious uses. Plant parasitic nematodes comprises one of the most important groups of pathogenic organisms prevailing around the root of medicinal plants causing reduction in plant growth and yield. Keeping this in view, an extensive survey was conducted in four districts of Uttarakhand namely Udham Singh Nagar, Nainital, Almora and Pithoragarh with 16 sub-location and 68 medicinal plants were found associated with 12 genera of plant parasitic nematodes. Soil samples were collected and identified on morphological basis for 200cc soil as Helicotylenchus spp., Pratylenchus spp., Meloidogyne spp., Rotylenchulus spp., Tylenchorhynchus spp., Tylenchus spp., Criconemoides spp., Aphelenchus spp., Xiphinema spp., Hoplolaimus spp., Trichodorus spp. and Ditylenchus spp. At Udham Singh Nagar, in location-1 (MRDC), Aloevera (Aloe barbadensis) exhibited maximum population and in case of nematode population Helicotylenchus spp. was predominant. In location-2 (Pantnagar), Mentha (Mentha piperita) recorded highest nematodes population and Helicotylenchus spp was highest. In location-3 (Palvika nursery), Tulsi (Ocimum tenuiflorum) recorded with population of all plant parasitic nematode and Population of Meloidogyne spp. was most prevalent among eight genera. In location-4 (Kashipur), Mentha (Mentha piperita) showed maximum population of and Population of Meloidogyne spp. was highest among all the nematode. In location-5 (CSIR CIMAP), Lemon grass (Cymbopogon flexuosus) recorded highest nematode population and Population of Helicotylenchus spp.,was most predominant In Nainital district, at location-1 (Kharina), Tulsi (Ocimum tenuiflorum) showed the maximum nematode population and Meloidogyne spp. showed maximum population density among all nematodes. In location-2 (Ramnagar), Ashwagandha (Withiana somnifera) recorded highest population of all the nematodes and Meloidogyne spp. population were maximum. In location-3 (Nainital), Stevia (Stevia rebaudiana) showed population of all the nematode and among the nematode population Helicotylenchus spp. was predominant. In location-4 (Haldwani), Bhrami (Bacopa monnieri) recorded the highest nematode population and Helicotylenchus spp. showed maximum population.In Almora district, at location-1 (Ranikhet), Mentha (Mentha piperita) showed highest nematode population density and Helicotylenchus spp. was highest. In location-2 (Majkhali), Tulsi (Ocimum tenuiflorum) recorded highest nematode population and Pratylenchus spp. exhibited maximum population. In location-3 (Chilliyanuala), Tulsi (Ocimum tenuiflorum) exhibited population of all the nematodes while population of Meloidogyne spp was highest. In Pithoragarh district, at location-1 (Forest nursery), Wild Carrway (Carum carvi) recorded population of all the nematodes and population of Tylenchus spp. was highest in all the tested medicinal plants. From location- 2 (Govt potato seed station), Puskar Mool (Inula racemose) exhibited maximum nematode population and Tylenchus spp showed maximum population. In location-3 (Tiksen farm), Chopcheeni (Samilax china) showed maximum nematode population and highest population was recorded by Helicotylenchus spp. In location-4 (Pithoragarh), Ashwagandha (Withiana somnifera) was most infected and population of Pratylenchus spp. was highest in this sample among all. In present study, altitude and soil moisture showed positive correlation with nematode population while Soil pH, Soil temperature and Organic carbon was found to be negatively correlated. On the basis of survey, it can be concluded that plant parasitic nematode are found to be in association with medicinal plant that may come as a serious threat to their cultivation and may serve as host for these nematodes in future.EnglishThesis