Meiotic Observations of the Microspore Mother Cells and Unreduced Diploidy Polleninduction in Manihot esculenta
Chromosome polyploidization through 2n gamate is one of the efficient approaches for plant genetic improvement.The rate of 2n gamete formation by artificial induction is much higher than that from natural formation.In this research,to find the efficient 2n gamate inductive period during the meiotic process of the microspore mother cells in cassava,different meiotic phases of the microspore mother cells closely correlated with the inflorescent and floral development and morphology were investigated.2n pollen were obtained through colchicine dip the flowers.The results showed that when the inflorence was 1.5 ~2.5 cm in length,the axilla inflorence initiated to grow,and the male flower bud was 1.0~1.5 mm in diameter,the microspore mother cells of cassava were in the meiotic stages of prophase I and metaphase I,in which the 2n gamete was efficient induction by dipping the flower buds with 0.3% colchicine +1% DMSO for 4 ~5 days.The rate of 2n pollen formation was up to 12.56% in SC5.