[2023] Does turrets contribute to plance defence?

That would be this one:

Disruption damage factor​

The ground mission wing can reduce any disruption left over after the escort phase further using its own stats. Finally the disruption produces a damage factor that scales the damage the mission can actually do. It uses the following components:

• disruption: value after the escort phase
• defense factor: air wing's defense divide by 200
• attack factor: air wing's attack divided by 200
• speed factor: air wing's speed divided by 1500
• air wing's number of planes (not reduced by mission efficiency)

The value that gets reported as "Planes disrupted" in the statistics of an air region is accumulated over all missions and sorties in the time frame.

Guided missiles always have a disruption damage factor of 100%, ignoring any disruption applied against them.  

GeneralisimoAR said: do you mean taht this:
"further using its own stats." referes to the bomber turrets???

In this case as the wiki states: any plane on a ground mission after the escort phase.