Serve with separate individual bowls of rice and oshitashi.
Heat a large nonstick skillet over high heat until hot, and swirl oil in. Place salmon, skin side down, in skillet; cook, undisturbed, for 2 minutes. Cook remaining 3 sides of fish until 70 percent cooked (it should be opaque on the outside yet slightly rare inside), 1 minute each side; fish should cook 5 minutes total.
Place each fillet on a plate and sprinkle with salt. Mound some daikon alongside each piece of fish and pour 1/4 teaspoon soy sauce over each mound. Garnish with lemon wedges, for squeezing.