Eight candidates have been officially confirmed to run in Russia’s 18 March presidential election.
Vladimir Putin, hoping to win a fourth term, is the clear favourite. Opinion polls give him a lead of more than 60percent.
Mr Putin comes fourth on the ballot paper, as candidates are listed in alphabetical order.
Police have repeatedly arrested opposition leader Alexei Navalny, who wanted to run for president but was barred. For years the anti-corruption campaigner has organised mass protests against Mr Putin.
Nicknamed the “strawberry candidate”, the 57-year-old engineer and farmer, is backed by the Russian Communist Party (CPRF).
Since 1995 Mr Grudinin has been boss of the Lenin State Farm – Russia’s largest strawberry grower, on the southern outskirts of Moscow. It supplies the capital with other fruit too, and boasted earnings of 2.3bn roubles (£29m; $41m) in 2014-2015.
The Soviet-era name may appeal to many older Russians nostalgic for the communist past. But the business is more efficient than most Soviet farms ever were; its strawberry harvest is as much as 60 tonnes daily.
During his election registration Mr Grudinin was found to have foreign bank accounts, which he is now reported to have shut down.
One official declaration from him on the electoral commission website, dated 8 January, specifies investments held at Liechtensteinische Landesbank. But another declaration, also from 8 January, says he has no money invested abroad.
On 16 January he said that he had opened foreign bank accounts to cover the cost of medical treatment for his mother and sister abroad, but that he had later closed the accounts.
Russian oligarchs are well known for squirrelling away fortunes in safe foreign banks, but that behaviour is not popular among poor, rank-and-file communists.
It suggests that Mr Grudinin is a “red capitalist” like some other Russian Communist politicians. In 1997-2011 he was an MP in the Moscow regional parliament.
In a TV debate he said “the communist idea united people” and “betrayal caused the Soviet Union’s collapse”. That nostalgia for Soviet-era power echoes President Vladimir Putin’s brand of patriotism.