** Shares of Australia's Pepper Money PPM.AX fall as much as 8% to A$1.545, hitting lowest level since June 2
** Stock logs worst day since March 17
** Non-banking lender rejects takeover approach from investment manager Challenger CGF.AX, citing execution concerns
** Offer valued PPM at A$1.01 billion ($706.19 million)
** CGF up as much as 5.6% to A$8.360, hitting highest since March 4
** PPM down nearly 25% while CGF down 11.9% this year, including the day's move
($1 = 1.4302 Australian dollars)
(Reporting by Rajasik Mukherjee in Bengaluru)
((Rajasik.Mukherjee@thomsonreuters.com))