The Level and Distribution of Chromosomal Aberration of Tomato Seeds at Different Penetration Depths of Carbon Ions

摘要

The relationship between the penetration depth and the level and distribution ofchromosomal aberration of the root tip cells were investigated by exposure of the superposedtomato seeds to 80 MeV/u carbon ions.The results showed that on the entrance of the beamthe chromosomal aberration level was low.Damage such as breaks and gaps were dominant.Atthe Bragg peak,the chromosomal aberration level was high.The yields of dicentrics,rings anddisintegrated small chromosomes increased but the yields of breaks and gaps decreased.Theseresults are consistent with the distribution of the physical depth dose profile of carbon ions.It iseffective to deposit the Bragg peak on the seeds to induce hereditary aberration in the mutationbreeding with heavy ions.