The variance of the pollen of 12 lines is highly significant ( = 0 . 01 ) and the variance of the different source mother root in the same diploid line is significant ( = 0 . 05 ) . the pollen of e type is bigger than the er type 从品系类型来看，丰产型材料的花粉粒直径稍大些，而两份抗丛根病材料的花粉粒直径较小。
