Chromosome number and karyotype analysis of Lactuca indica

Lactuca indica is a good pasture resource,mature period is a key for L.indica being used effectively.In this paper,the root tip of L.indica was pretreated with ice-water,chromosome dyeing used acetic acid magenta.The karyotype analysis results were as follows: the chromosome numbers of two varieties of L.indica(early mature L.indica and late mature L.indica) are equal(2n=2x=18).The karyotype formula of the early mature L.indica is 2n=2x=2m+12sm+4st;and the karyotype formula of the late mature L.indica is 2n=2x=16sm+2st.