Hi Hamza,

Have you seen this original paper about constructing D2 and R2 transgenic lines (see attachment). They has constructed 6 lines (D1, D2, D3, R1, R2 and R3) to study 'recombination' effect in Arabidopsis by using GUS gene. The 'D' stands direct orientation of 2 engineered introns in the GUS gene, while 'R' indicates reverse orientation of 2 engineered introns in the GUS gene (please see the yellow highlights in the paper). R1, R2 and R3 were constructed in binary vector pBI121, which has a nptII gene and confers kanamycin resistance. So, you can see at the yellow highlighted paragraph, they used Kanamycin as selection agent. The L1, L2, L3,..... was line 1, line 2,...etc. So, you should use kanamycin to select R2L1.

The concentration of kanamycin used for Arabidopsis selection is pretty standard.

I am guessing that you are trying to cross these lines with other mutants to see whether the recombination rate will change.