Evaluation of resistance to Fusarium oxysporum f.sp. sesami in hybrid lines of sesame (Sesamum indicum L.) under greenhouse conditions

Abstract

Thirty-six samples of sesame (15 F1 and 15 F2 generations and their 6 parents) were evaluated for their reaction to Fusarium oxysporum f.sp. sesami (Zaprometoff) Castellani after artificial inoculation in greenhouse tests. The experimental soil was analysed mechanically and microbiologically. Reactions of the plants were recorded on a scale from 0 = no visible infection (immune) up to 6 = 70% infected plants (highly susceptible). Highly significant differences of susceptibility and resistance to the wilt pathogen were observed among hybrids and their parents. The level of infection in the parental generation varied from 2.22 to 63.77% (mean at 33.74%), in the F1 from 13.46 to 73.78% (mean at 32.09%), and in the F2 populations from 0.71 to 59.4.5% No population was immune. Nine lines of the F1 were classified as resistant (R) and three of them had the same rank in the F2. Only one parent (P3) and three lines from the F2 (13, 9 and 12) showed infection below 10% and were identified as highly resistant (HR) by infection rates of 2.22%, 0.71%, 6.08% and 9.57%, respectively. They can thus be considered as promising parents for breeding programs.

Keywords

• sesame
• fusarium wilt
• wilt resistance, disease resistance