You're inferring a transcriptional network using ARACNe, correct? Then the chip ID you need entirely depends on what chip your microarray data comes from. Given that you appear to be using this paper for reference, you need to convert it to the probe ID for the Affymetrix Cotton Genome Array.
Searching the Plant TFDB for BES1 yields this result. Scroll down to the "Expression" information, and it gives you the GeneVestigator ID 259955_s_at, which happens to be the probeset ID for the Affymetrix Arabidopsis ATH1 Genome Array.
Now go to the PLEXdb Blast, input the Arabidopsis ID, specify the Arabidopsis ATH1 22k, and then indicate that you want to covert it to the Cotton platform. The top result is Ghi.9165.1.S1_s_at, and checking this against the annotation provided by Affymetrix themselves this seems to be correct.