Secondly, in order to obtain normal haploid plant, the selection of growth regulators
and their ratio become critical. Since regenerated plant derived from anther culture is
sometimes tetraploid or mixploid besides haploid and diploid. It happened probably
during the anther in vitro culture, callus induced medium and differentiation medium
contained many kinds of plant growth regulators, which led to cells unusual mitosis,endoreduplication, nuclear fusion, appearance of polyarch spindle or chromosome nondisjuction
[Lin et al. 2010]. Besides, the proportion of growth regulators strongly influences
the formation of normal and abnormal roots. Plantlets with abnormal roots are
always characterized by no primary roots, primary roots cracked, split primary roots,
stubby primary roots with no secondary roots and even roots missing.