The effect of gamma radiation on callus growth and plantlet regeneration of four tomato hybrid Lycopersicon esculentum mill In vitro

Abstract

Calluses were induced from four tomato hybrid (Davista, superDavista, Muntcarloo,Hymar). On MS medium supplemented with 2, 4-D Auxin at concentration of 4 mg/L.The Callus were divided into two groups the first one was affected with gammaradiation at the doses (0,2,4,6,8)Gray and re cultured on the same mentioned medium.The second group was also affected with gamma radiation with the same dosesmentioned above and re- cultured on MS media supplemented with 0.5 mg/L Kinetinfor regeneration. Fresh and dry weight was measured after 8 weeks. The number andlength of shoots were measured as indicators after 6 weeks. Results revealed that thedose 2 Gray was superior to give highest rate of fresh and dry weight reaching 238.5and 43.1 mg respectively and the hybrid super Davista was superior in giving thehighest fresh and dry weight reaching 231.6 and 30.2 mg respectively. Moreover theresults revealed that control treatment was superior in giving the highest rate innumber and length of plantlets. The 2 Gray treatment showed a significant effect onthe rate and length of plantlets. In addition, there were significant differences amongthe cultivars in most characters mentioned above.