The methods to doubled pollen chromosome of Avignon were studied.Using flower buds of Avignon as materials,the meiosis processes of pollen mother cells were observed.In order to know when 2 n pollen could be induced,the relations between flower buds length and pollen mother cells developmental stages were studied.Then it induced doubling pollen chromosome with various concentrations of colchicines in different treatments.The results indicated that the best time for 2 n pollen induction was that the length o...