Temperature sensibility analysis and hybrid seed purity identification of pepper yellow-green seedling mutant ecotype sterile line

ObjectiveTemperature sensibility of yellow-green pepper mutant ecotype sterile line YBM-EAB12 were analyzed to provide reference for the resources exploitation and utilization of thermo-sensitive characters of yellow-green pepper.MethodThe pepper materials YBM-A2,YBM-EAB12,YBM-A2×C and YBM-EAB12×C were respec-tively induced under the temperature conditions where day temperature/night temperature were 20℃/15℃,25℃/20℃and 30℃/25℃.Then the pepper materials were planted and managed in the greenhouse.The pollen quantities and pollen germination rates of pepper materials were observed;fertility of parents was researched.Morphological identification and seed purity identification were also conducted.ResultYBM-EAB12 enjoyed temperature sensibility.The critical tempe-rature of fertility transformation for YBM-EAB12 was 22.5℃.Under low temperature conditions(daily average tempera-ture was below 22.5℃),YBM-EAB12 was fertile and self-fertile.The lower daily average temperature,the higher fertili-ty.But under high temperature conditions(day temperature/night temperature was 30℃/25℃),YBM-EAB12 was com-pletely sterile.The trait of yellow leaf were controlled by a pair of recessive nuclear gene.According to YBM-EAB12×C F2population segregation results,cytoplasmic male sterility(CMS)was tightly linked to the organ characteristics of sterile flower.The fertility of YBM-EAB12×C F1was restored by mononuclear dominant gene and was not affected by low tem-perature.ConclusionPepper yellow-green seedling ecotype sterile line has the characteristic of fertility under low tem-perature.Breeding the sterile line with pepper yellow-green seedling ecotype sterile line can reduce the step of hybridiza-tion between sterile line and maintainer line,reduce seed production step of third-line breeding in pepper sterility lines.It simplifies seed production procedure.