If there are 24 chromosomes in plant cell g1 what is the diploid number

The answer to this question would be: 24 chromosomes

In G1 phase, the cell is preparing for a division. The chromosome is not duplicated yet, make the number of chromosomes will be same as normal diploid cells.  That means the number of chromosomes in the cell at G1 phase will be same as normal cells. 
The chromosome will be duplicated in S phase which was the phase after G1.