"Sekuhara" is Japanese for "sexual harassment". And no, the daikon are not actually making noises.
Created by a young artist named Etsuko Ichihara, this multimedia project debuted a few years back. The set up apparently uses electrical capacitance pressure sensors to detect when the vegetables are being "touched", causing pre-recorded sound effects. Warning: the noises sound like porn moans.
As Kotaku Japan points out, daikon is a traditional winter food in Japan. But if you really think about it, the Japanese giant radish can represent both the female and the male.
If you want to see Ichihara with a blinky nipple apron stab, spank, and stroke various daikon on against their will (lady, they're saying "stop it!), there's this video. It also contains a stuffed dog making porn groans. Performance art!
HENTAI大国日本、ついに大根を喘がせてしまう [Kotaku Japan]