randomreads.sh adding abundances for metagenomic like distribution

Hi,

I have 9 genomes, I would like to produce a metagenome like distribution using randomreads.sh. I concatenated genome fasta files in one reference file. Then, ran as below.

../bbmap/randomreads.sh ref=simplified_catgenome.fasta out1=20M.read1.fastq out2=20M.read2.fastq length=125 paired=t metagenome=t genome=9 reads=20000000

However, I would like to know if there is any way I can define the abundances for each genome based on qPCR results and then produce the reads accordingly. Would there be a way to produce reads from each genome separately with the absolute abundances?

Thank you!