Forward Valbuena (pictured) was rewarded for helping Olympique Marseille win the Ligue 1 title and Girondins defender Planus will provide cover for central defender William Gallas who is still struggling with a calf injury.
Domenech, who has until June 1 to name his official 23-man squad, is still hoping Gallas will be able to take part in the June 11-July 11 finals in South Africa.
The France coach dropped goalkeeper Mickael Landreau, defenders Rod Fanni and Adil Rami, midfielder Yann M'Vila and forwards Hatem Ben Arfa and Jimmy Briand.
Domenech, who has faced criticism since his side's Euro 2008 flop and is booed by the France fans at every game, has one last chance to become popular at the World Cup, after which his contract will end.
France, who needed Thierry Henry's infamous handball to qualify for the finals through a playoff at the expense of Ireland, start a week-long training camp in the French Alpine resort of Tignes on Tuesday.
