Abstract: In order to investigate the relationship between the development of hermaphroditic and male flowers in Asparagus officinalis L. and the carbon and nitrogen compounds, the content of carbon and nitrogen compounds were determined in hermaphroditic and male flower buds of asparagus at three representative stages of early, middle and late sex determination. And the alternative splicing and expression of nitrogen compounds in six samples was analyzed by RNA-seq technique. The results showed that the carbon content of hermaphroditic flower buds was lower than that of male buds. On the contrary, the nitrogen content was significantly higher than that of male buds at the early and middle stages. At the late stage, the carbon content of hermaphroditic flower buds was equal to that of male buds, but the nitrogen content was still significantly higher than that of male buds. It was found that lower C/N was beneficial to gynoecium differentiation in hermaphroditic flower buds. Moreover, it was shown that 86 nitrogen compound metabolic related genes were alternatively spliced only in hermaphroditic flower buds by RNA-seq and GO enrichment analysis and these genes mainly encode ribosomal proteins, MADS-box transcription factors and some enzymes. At the early and middle sexual differentiation stages, there were 52 and 47 of the nitrogen compound metabolic related genes in hermaphroditic flower buds which expressing higher than those of male flower buds, respectively. This was consistent with the difference in nitrogen content between hermaphroditic and male flower buds. In conclusion, it was obviously that the alternative splice of nitrogen compound metabolic related genes and their high expression, and the lower C/N were beneficial to gynoecium differentiation in hermaphroditic flower buds.

Key words: Asparagus officinalis L., Hermaphroditic flowers, Male flowers, Carbon-nitrogen ration, Alternative splicing

CLC Number: 

• S644.03