"There is a dispute going on in Mulayam's family. He is contesting from here (Azamgarh) to please his second wife and pave way for their son Prateek Yadav," she told an election rally here.
On Chief Minister Akhilesh Yadav referring to her as his 'bua' (aunt) at a recent public meeting in Uttar Pradesh, Mayawati said it would be an "insult" even to consider him as her younger brother.
"Akhilesh used to insult dalit icons. He terms construction of memorials in their names as wastage of money despite the fact it generates income for the state," she said.
Taking potshots at Mulayam and Akhilesh, Mayawati said, “They should understand that it was due to B R Ambedkar they are here, otherwise they will be grazing cows and buffaloes in fields."
Asking Yadav community to wake up, Mayawati said they should come out of Mulayam's "mental slavery".
Alleging that the SP and BJP had tacit understanding, Mayawati said Narendra Modi was contesting from Varanasi and Mulayam from Azamgarh due to their pact.
Had Mulayam wanted to prevent Modi from winning, he should have contested from Varanasi, Mayawati said.
Mayawati alleged Mulayam would leave Azamgarh after the elections.
"While Modi will leave Varanasi and retain Vadodra, Mulayam will retain Mainpuri," she said.