The Getaway presenter, who has two children with husband James Pettit, was believed to be either teaming up with Kennerley or taking over Mornings with Kerri-Anne after being asked to host the programme in her absence this week.
However, Rowntree has insisted that she has enough on her plate with her Geelong farm, family and Getaway and will not be joining the show.
She told The Daily Telegraph: "I know there's a lot of talk at the moment but all I know is that I got a call asking to fill in and there's not much else to it. People aren't aware how hard Kerri-Anne works - hers is a full-on gig. She's on a well-earned break.
"And the reality is I live on a farm and I have two little boys. Even if anything did eventuate, I just don't know how we could make it work the way my life is right now. Plus I'm contracted to Getaway all of next year. Sorry to be boring."
Rumours that Kennerley was quitting her morning programme and being replaced by Rowntree surfaced for the first time last year. Rowntree said at the time that she would not be interested in the job, even if the reports were true.
Kennerley's contract with the Nine Network is currently up for renewal and bosses are reportedly keen to replace the single host with a panel of presenters similar to The Circle following a slump in viewer ratings.
A Nine spokesperson said yesterday that "many" celebrities have previously stood in for Kennerley - including singer Kate Ceberano and Domestic Blitz presenter Shelley Craft - and added that no format changes have been decided yet.
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