Preliminary Analysis of B Chromosomes in Maize Landraces from Southwest China
B chromosomes(Bs) in 54 maize landraces from Southwest China were tested by means of cytological observations.Its general characteristics was found in the B chromosome of maize landraces.The aberrant distribution and separation of B chromosomes might result in their differences in plant individuals and cells.Out of 54 maize landraces,nine landraces with Bs were observed.The number of Bs was found variable.The number of Bs in the landraces ranged from 0 to 7 and varied from 0 to 3 in a single cell.The 12.96%,5.56% and 3.70% of the total landraces were found with 1Bs,2Bs and 3Bs.It was indicated that southeastern Sichuan was the main distribution area of the landraces with Bs in Southwest China.