< b > EVALUATION OF SESAME GERMPLASMS FOR RESISTANCE TO < i >FUSARIUM OXYSPORUM f .sp.< i> SESAMI < i.>< /b > A. FASSIHTANI Fars Agricultural Research Center. P.O.Box 73415-111, Fars. Zarghan, Iran < b> Background and objectives< /b> Sesame wilt caused by Fusarium oxysporum f. sp.sesami < /i > is considered to be the most serious disease and causes considerable losses to the crop. [ 1]. The strategy for controlling Fusarium wilt i s based on planting in noninfested soil, the use of clean seeds, and rotation with non-host species. The use of resistant varieties would be more effective and ecologically sustainable. Goyal et al.[2] evaluated 206 local and wi ld sesame cultivars against the pathogen, and found only 3, tolerant cultivars. In this work, 85 sesame germplasms were screened against wilt disease under natural field-conditions. < b>Materials and Methods< /b> A diseased infected plot with a history of Fusarium infection was prepared by planting a susceptible cultivar Darab-2, consecutively for two years in Zarghan Station. In addition, wilted sesame plants were collected from infected fields, dried, chopped, and uniformly added to the soil in order to build up the inoculum in the infected plot. Eighty- five sesame germplasms collected from all over Iran were sown each in two replicated plot rows measuring about 5 meter. Disease incidence and severity index were estimated on the basis of external symptoms and discoloration in the stem. Results and Conclusions In the present investigation 85 sesame germplasms were screened against F.oxysporum f.sp.sesami under natural field conditions.Based on the disease evaluation indices, the tested sesame could be classified in four groups. The results indicated that two of the 85 accessions were found moderately resistant, 6 were tolerant, 19 were moderately susceptible, 31 were very susceptible and 23 accessions were wilted prior to flowering and classified as susceptible to Fusarium wilt of sesame. Resistant sesame lines, 85 and 54 possess good agronomical characters, so they constitute a valuable germplasm in sesame breeding for Fusarium resistance. References [1] Banihashemi,Z.1982.Tran.J.Plant pathology 17,75-79. [2] Coyal,S.N, & Patel,P.K. 1980.Gujarach Agric.Univ. Res.J.5(2)52-53.