Table 1.

Comparative evaluation of two studies (English and American) of tolerance of Ceratocystis ulmi to methyl-2-benzimidazole carbamate by relative factors.

Factors relative to toleranceBrazier & Gibbs (English, 1975)Schafer (American 1976)
1. Pathogenicity--
2. Mating--
3. Asexual stage Frequencya (Conidia)+ 1-1.3 × 108+ 1-1.3 × 108
4. Sexual stage Frequencyb (ascospores)Not tested1-1.9 × 108
5. Mendelian segregation++
6. Stability of tolerant mutations++
  • a 1 in 130,000,000

  • b 1 in 190,000,000