By Wa Lone

YANGON (Reuters) - Myanmar's powerful army chief and Aung San Suu Kyi, head of the newly elected government, made a rare public appearance together on Tuesday during annual celebrations of independence hero General Aung San, Suu Kyi's father.

Relations between Min Aung Hlaing, the head of the armed forces, and Suu Kyi will define the success of Myanmar's emergence from decades of isolation and military rule that began when the army seized power in 1962.

For the first time in years, the army chief paid respects at a mausoleum dedicated to Aung San. He and other military officials also visited Suu Kyi's house, where the Nobel Peace Prize winner spent 15 years under house arrest.

"Platoons, raise your arms - salute fallen leaders," a soldier said in a loud voice as ministers and parliament members bowed their heads, while military men saluted to the sound of trumpets at Yangon's Martyrs' Mausoleum.

"This behavior will help promote the military's respect among the people," said Aung Shin, historian and editor of D-Wave journal, a publication of the National League for Democracy party led by Suu Kyi.

Aung San has remained a powerful force in Myanmar's politics in the 69 years since his death. His image has been used not only by Suu Kyi but also by her political rivals to give themselves legitimacy and gain popular support among a public that still largely reveres him.

That admiration was on full display on the streets of Yangon, where hundreds of people wearing headbands, colorful T-shirts with Aung San's name and inscriptions "We won't forget July 19" lined up to visit historic sites related to him.

"I feel like this time is very different from the previous five years I've attended this ceremony," said Zaw Zaw Aung, 22.

Aung San fought with the Japanese against the colonial British who ruled Myanmar, then Burma, during World War II, before switching sides to drive out the Japanese and set Myanmar on the path to independence.

On July 19, 1947, Aung San, then 32, was gunned down along with several colleagues by political rivals. The assassination plot has never been fully explained. A year later, Aung San's dream of an independent Myanmar was realized.

In death, he became a symbol of Myanmar's struggle for independence. But use of his image was curbed by the military junta starting in 1988 for fear of bolstering his daughter, who had returned to Myanmar from England and emerged as the leading figure in the country's democracy movement.

(Editing by Hugh Lawson)