Nirmaladevi, SBiju, DanielKAU2019-05-282019-05-282003http://krishikosh.egranth.ac.in/handle/1/5810105201PGAn investigation on "Screening of tomato somaclones for resistance to Tomato Leaf Curl Virus" was undertaken in the Department of Olericulture, College of Horticulture during 2000 - 2002 to standardize the explants of L.esculentum var. 'Sakthi' and; to standardize the media for callus induction, organogenesis and shoot induction in tomato and to screen the somaclones of bacterial wilt resistant 'Sakthi' and L. pimpinellifolium for resistance to Tomato Leaf Curl Virus. The leaf segments exhibited high callus index in the MS medium supplemented with NAA (2 mgl") and BA (1 mgl', 2 mgl' and Jrngl") for 'Sakthi' and L. pimpinellifolium. The basal medium containing NAA (1 mgl") and kinetin (4 mgl") gave maximum callusing in internodal segments of' Sakthi'. In the case of nodal segments MS medium supplemented with NAA (1 mgl") and BA (4 and 5 mgl") recorded early callusing and highest callus index in both' Sakthi' and L. pimpinellifolium. The percent morphogenic capacity was highest in internodal calli (95%) followed by leaf segment calli (88.8%) in 'Sakthi' when basal medium supplemented with NAA (2 mgl !) and BA (3 mgl"). In 'Sakthi' the highest percent root growth and maximum number of root hairs was obtained in MS medium with IBA (1 rngl"). In L. pimpinellifolium percent root growth was maximum in the medium containing IBA (0.5 mgl") and IAA (1.5 mgl"). Screening of somaclones of 'Sakthi ' and L. pimpinellifolium for resistance to TLCV disease, transmitted by white fly Bemisia tabaci has revealed that two somaclones of 'Sakthi' were free from the disease and five plants exhibited mild symptoms. Two somaclones yielded higher than control and another two plants were free from fruit cracking. The somaclones of L. pimpinellifolium were free from TLCV disease. However the resistance to the disease improvement in horticultural traits can be confirmed only in subsequent generations.ennullThesis