Reporters Without Borders (RSF) said it "marks a disastrous turning point for the freedom to inform in Georgia."
Prominent Georgian TV personalities and managers have accused prime minister Irakli Garibashvili's government of setting violent hate groups against critical media.
"Garibashvili must resign. All those who attacked journalists on 5 July must be prosecuted," the protesting TV stations said in identical statements on their Facebook pages.
Instead of regular programmes, the four national broadcasters were showing a scrolling list of more than 50 journalists who sustained injuries in last week's attacks including concussions, chemical burns and broken arms.
"Our silence will shout loudly about the incredible challenges independent media face in Georgia," Pirveli TV's news editor, Nodar Meladze, told AFP.
Hundreds of journalists turned out on Tuesday for Lashkarava's funeral, which saw his coffin carried through a corridor of colleagues with their cameras lowered on tripods.
Garibashvili expressed condolences to Lashkarava's family and colleagues and promised a prompt investigation into the cause of his death, which he has called an "incredible tragedy."
The United States and European Union have condemned the attacks on journalists and called for the prosecution of those responsible