Oct 31 (Reuters) - Australia's Nitro Software (NTO.AX) said on Monday it would back a near A$500 million ($320.15 million) offer from KKR Inc's (KKR.N) Alludo that trumps an earlier bid from major shareholder Potentia Capital Management. Shares of Nitro Software rose as much as 19.1% to A$2.06 in morning trade, the highest point since January. In a statement, Nitro said the Alludo offer was fully funded by "equity sources", without identifying the backers. Potentia has built a 19.8% stake in Nitro and declined to comment on the Alludo offer. Last week, ELMO Software (ELO.AX) agreed a $A500 million takeover from Los Angeles-based K1 Investment Management.

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