Abstract: The developed smearing method was adopted to observe the process of PMC meiosis of 'Tainong 1' and 'Irwin' (Mangifera indica L.) in this article. Results were as follow: The cytoplasm devision of mango PMC was simultaneous type. under normal temperature (25-30℃), the process of pollen mother cell meiosis is normal; The most of chromosomes become bivalents which like "V", "O", "Y", "X", sticks and dots, and mainly like dots, "V" and "O"; and a few of univalent (0.79% of Tainong 1 and 0 of Irwin) and multivalent (4.76% of Tainong 1 and 3.57% of Irwin) had been observed. While under natural low temperature (10-20℃), a great deal of abnormalities, including micro nucleoli, scattered and lagged chromosomes and anaphase bridges were detected during PMC meiosis, even though the abnormalities were different between the two cultivars; the ratio of micro nucleoli was 22.88% of average, which was obviously higher than that of control (4.56% of average under normal temperature); and the ratios of univalent and multivalent in diplotene, which increased seriously, were 8.82% and 17.65% of Tainong 1, and 14.52% and 24.19% of Irwin under natural low temperatures. Abnormalities during meiosis under natural low temperatures might play a role in male sterile.

Key words: Mangifera indica L., low temperature, meiosis, abnormality