Measurement Of Flowering Time And Analysis Of Gene Expression In Brassica Rapa

Brassica rapa is an important vegetable and oil crop belonging to cruciferae brassica.It is extensively grown in the whole world.Brassica rapa involves complex hereditary basis,and has many important agronomic traits such as flowering time,leaf shape and chlorophyll content.Flowering signifies that the plant transforms from nutritive growth stage into reproductive growth stage.Flowering is regulated and controlled by environmental factors?such as vernalization and light period?and growth conditions of vegetable cells.Flowering time has important significance for breeding of Brassica rapa,and the time of flowering will also influence the commodity quality.It has important theoretical and practical values for genetic improvement to observe and analyze the flowering time character of Brassica rapa with different origins.In this paper,464 crops of brassica rapa collected in Asia and Europe were set as research materials,and their flowering time was observed.The three genes related to flowering time?BcFLC1_A10,BcFLC2_A02 and BcCCA1_A05?were treated under different durations of sunshine.Through real-time quantitative analysis,the following research results were gained:1.The 464 crops of brassica rapa were sowed in the test field of Jiangpu Farm in Nanjing Agricultural University.SPSS analysis was conducted for flowering time of brassica rapa belonging to different groups.According to the results,the average flowering time of SO is 69.75 days,so it is classified into extremely early flowering group.The average flowering time of BRO is 137.78 days,so it is classified into early flowering group.The average flowering time of OR is 144.76 days and the average flowering time of WO is 158.16 days,so they are classified into medium flowering group.The average flowering time of PC is 172.28 days,the average flowering time of CC is 176.25 days,and the average flowering time of WTC is 174.47 days,so they are classified into relatively late flowering group.The average flowering time of VT/FT is 201.36 days,so it is classified into late flowering group.2.BcCCA1 of non-heading cabbage was cloned,and a homologous comparison was made with relevant genes of other plants.According to the results,the similarity between BcCCA1 of non-heading cabbage and relevant genes in turnip?NC₀24799?,arabidopsis?NC₀03071?and camelina sativa?NC 025689?reaches 99%.Moreover,subcellular localization analysis was conducted for the expression protein of BcCCA1.It might exist in cell nucleus or cytoplasm.3.Expression analysis was conducted for BcFLC1,BcFLC2 and BcCCAl in 11 kinds of brassica rapa treated under different light periods by utilizing real-time quantitative technique.According to the results,under long sunshine condition of 16h sunshine/8h darkness,the expression quantity of BcCCA1 in brassica rapa decreases obviously during 1-16h of sunshine and increases significantly during 17-24h of darkness.The expression quantity of BcFLC1 and BcFLC2 decreases slightly during 1-16h of sunshine and increases slightly during 17-24h of darkness.Under short sunshine condition of 8h sunshine/16h darkness,the expression quantity of BcCCAI in 11 kinds of brassica rapa decreases during 1-16h of sunshine,but its decrease is not as obvious as that under long sunshine treatment;it increases during 17-24h of darkness.The expression quantity of BcFLCl and BcFLC2 does not present significant increase or decrease under short sunshine condition of 16h darkness/8h sunshine.