Andrew Hooper, who has now lost the ability to speak due to severe facial injuries, is alleged to have murdered 51-year-old Cheryl Hooper with a shotgun on January 26 last year before turning the weapon on himself.
Birmingham Crown Court was told the 46-year-old shot Mrs Hooper in the neck from around 1.5 metres away because he was "consumed with anger and jealousy" after she left him at the end of 2017.
A jury panel of five men and seven women was told Hooper, described as a "controlling individual" by the prosecution, had tracked his wife's car, spotted her with a man called Ian Preece, returned to his farm to collect a shotgun and "ambushed" her outside her house.
The prosecution said that when Hooper saw his wife with Mr Preece "the straw had broken the camel's back".
The court heard the alleged victim's 14-year-old daughter had seen Hooper "look like a psychopath" with "murder in his eyes" before killing her mother.
The Crown described the alleged murder as a "cold-blooded, ruthless and callous execution".
Opening the case against Hooper, of Guild Lane, Newport, David Mason QC prosecuting, told the jury: "The case that you are about to hear is a tragedy of unbelievable proportions.
"Many people have been affected by what happened on the night of January 26 last year. Including, as you can see, the defendant.
"On that night, that man shot his wife dead right in front of her 14-year-old daughter, before fleeing the scene, returning home and then turning the gun on himself and firing one more time."
Mr Mason continued: "Whether he actually intended to kill himself and missed, perhaps we will never know.
"Was shooting himself and missing one last cowardly act from a man that had just destroyed another life?
"Perhaps it doesn't matter. Because what does matter, really matter, is that, we say, he intended to kill his wife."
Mr Mason then showed the jury CCTV of Hooper carrying an item under a blanket to his Land Rover which "had a shape consistent with a shotgun".
He continued: "It was a brutal and cowardly act, committed by a man who was clearly consumed with anger and jealousy.
"He will, I expect, during the course of this trial try and persuade you that what happened was an accident and that all that he had meant to do was to frighten Cheryl, his wife.
"We, the prosecution, will show you that this was a deliberate and calculated act and that the only intention that this man could possibly have had that night was to kill his wife."
Describing the events leading up to the alleged murder, Mr Mason said: "Whatever he may have been saying to Cheryl publicly, privately his jealousy raged to an uncontrollable level.
"He tracked her car, without telling anyone. He obtained another shotgun, secretly held, despite having handed over the ones that everyone knew existed.
"He waited until when he knew that she was going out. He followed her and when he caught her with another man, he calmly returned to his farm, collected the shotgun, ambushed Cheryl outside her house... having loaded and cocked the weapon and brutally ended her life in front of her daughter."
He added: "(This is) a case that will leave you in no doubt that this man is a cold-blooded murderer and that when that weapon went off that night, not once, but twice, he had no intention other than murder."
Referring to the injuries Hooper has been treated for since the alleged incident, Mr Mason said the defendant can now only communicate through a keyboard.
He said: "Because he cannot speak, the police interviews were very slow and laborious.
"He tapped his answers out on a keyboard, which is what will have to happen during this trial, if he gives evidence from the witness box."
Hooper, of Guild Lane, Newport, Shropshire, denies murder.
The trial continues.