AGRICULTURAL RESEARCH COMMUNICATION CENTRE www.arccjournals.com Agric. Sci. Digest., 34 (3) : 226 - 228, 2014 doi:10.5958/0976-0547.2014.01008.8 SCREENING OF DIFFERENT SUNFLOWER VARIETIES AGAINST ROOT-KNOT NEMATODE (MELOIDOGYNE INCOGNITA) IN JAIPUR, RAJASTHAN Shilpi Rajput* and Payal Lodha Tissue Culture and Biotechnology Laboratory, Department of Botany, University of Rajasthan Jaipur-302 004, India Received: 05-11-2013 Accepted: 28-04-2014 ABSTRACT This study was carried out to screen various Helianthus annuus varieties against root-knot nematode (Meliodogyne incognita) infections in Jaipur district. Eight varieties were tested against nematode infection i.e. The variety CO1 was proved to be most tolerant against root knot nematode infection without any gall (0). MODERN Variety was the most susceptible variety to root knot nematode infection with gall number 50.6. KBSH-41 was found resistant with gall number 8.6 while number KBSH-1 and KBSH-44 were found moderatetly resistant with gall number 15.6-21.2. KBSH-53, DRSF- 108 and DRSH-1were found susceptible with gall number 31.8-34.5. Key words: Nematode, Sunflower, Variety, Meliodogyne incognita, Resistant. *Corresponding author’s e-mail:shilpirajput007@gmail.com INTRODUCTION The root-gall nematode, Meloidogyne species attack more than 2000 species of plants Nematodes are probably one of the most interesting multicellular animals found in the world. The root-gall nematode, Meloidogyne species attack more than 2000 species of plants. A gall on host plant can reveal all structural modifications which the plant has potential to produce. (Dropkin 1955; Singh 2006; Raghav 2007). They are a large ubiquitous group of invertebrates with representatives in almost every kind of environment. Many of them feed on higher plants and damage them. They affect both crop yield and quantity, and limit utilization of nutrients by plants, thus causing wastage of fertilizers. Root knot is one of the most common problems associated with crops, especially oil yielding crops in the tropical and sub-tropical climates. When susceptible plants are infected at seedling stages, losses are very severe and may result in complete destruction of the crop. Sunflower (Helianthus annuus L.) is the second most important oilseed crop in the world after soybean. The acreage under sunflower cultivation in India has been on a constant increase. This crop as an oil seed crop was introduced in India during 1969 with the object of bridging the gap between the production and consumption of edible oil in the country (Burney et al., 1990). The acreage under sunflower crop is on the increase since then. Nematodes cause significant losses in the crop yield. According to an estimate by the United States, Department of Agriculture (USDA) total loss due to nematodes is $ 4 x109 per annum (James, 1981). Amongst nematodes, root knot nematode Meloidogyne incognita has also been proved to be a threat to sunflower crop. Root knot disease of sunflower is becoming one of the most serious problems for the successful cultivation of sunflower crop. On account of alarming losses (16.44% yield losses) it requires immediate and due attention to minimize its predation. Among various control measures screening of resistant varieties is the most economical mean and economical component of IPM package for controlling plant parasitic nematodes. Keeping in view the economic importance of root knot nematode M. incognita present studies were planned to screen out the different cultivars against ro o t kno t nematode M. incognita. MATERIALS AND METHODS Collection of root samples: All the experiments were carried out in the Botanical Garden, Department