Abstract:

【Objective】 Transmission of the n+1 gametes of flowering Chinese cabbage-Chinese kale monosomic alien addition lines was studied in order to lay a basis for application of the gene localization and genetic improvement. 【Method】 The frequencies of n+1 gamete formation in different monosomic addition lines were assessed by a rate of PMCs with 10/10/11/11 segregation at anaphase Ⅱ. The transmission rates were determined by examining the chromosome number of plants derived from the populations of the different monosomic addition lines crossed with the flowering Chinese cabbage, respectively. The bisomic addition lines were selected from the selfing populations of the monosomic addition lines. 【Result】 The frequencies of n+1 male gamete formation in different monosomic addition lines were 36.85%-45.15%. The transmission frequencies of the monosomic addition lines varied from 7.14% to 14.81% for male gametes and from 19.07% to 36.51% for female gametes. There were no obvious associations of the n+1 gamete transmission rates with the n+1 gamete formation rates, chromosome size, pollen amount and pollen viability. Two different bisomic addition lines of the flowering Chinese cabbage-Chinese kale were identified from the selfing populations of the monosomic addition lines. 【Conclusion】 The extra chromosome of the flowering Chinese cabbage-Chinese kale monosomic addition lines can be transmitted by both female gametes and male gametes, but the transmission rates varied with the different monosomic addition lines, and the bisomic addition lines can be obtained from the selfing progeny of the monosomic addition lines.

Key words: flowering Chinese cabbage (Brassica campestris L.var. utilis Tsen et Lee), Chinese kale (Brassica alboglabra Bailey), addition lines, formation and transmission of n+1 gametes