Various programmes were held across Goa to mark the occasion.
Parrikar, 63, has been recuperating at his private residence near here since October 14, after he was discharged from Delhi's All India Institute of Medical Sciences (AIIMS).
Goa was freed from the Portuguese dominion on December 19, 1961 after a freedom movement and Army operation. It was granted full statehood in 1987.
In his 10-minute speech made in Konkani, Sawant touched upon Parrikar's inability to attend the event on medical grounds.
"The state government is trying hard to make Goa plastic and pollution free, but the efforts can become fruitful only with the active participation of citizens. On this day, let us take the pledge to make Goa free of plastic and pollution", he said.
Lakhs of tourists visit Goa every year for its picturesque beaches.
The problem of plastic items being dumped haphazardly by tourists at various beaches is a cause of concern for the administration as well as environmentalists.
During his address, Sawant listed out various developmental programmes, infrastructural works and employment generating initiatives taken up by the BJP-led government with the help of the Centre.
"Completion of two bridges over Mandovi and Zuari rivers, in addition to the existing ones (bridges), will help streamline flow of traffic from North Goa to South Goa", the speaker said.
Sawant also recalled the sacrifices made by freedom fighters and citizens to get Goa liberated from the 450-year rule of the Portuguese in 1961.
He also hailed the Indian armed forces for pushing the Portuguese military out of the state in 1961.
Meanwhile, addressing a gathering in Margao in south Goa, GFP leader and state Town and Country Planning Minister Vijai Sardesai stressed the need to liberate oneself from "regressive ideas, pseudo activism, external interference and patronising attitudes".
"Liberation of Goa happened in 1961, but we should remember that liberation is a continuous process and it can never be over", said the minister whose Goa Forward Party (GFP) is one of the constituents of the BJP-led coalition government in the coastal state.
"Only adversaries have changed since 1961. We have new threats from inside and outside. We also have to liberate ourselves from our prejudices, negativity, dogmas and petty rivalries. We should also liberate ourselves from dependence to take Goa forward", he said.
Underlining the need for "neo-liberation", the minister said, "we need neo revolutionaries, neo-activists and neo-Goemkars (Goans)".