HEAT oil in large skillet over medium-high heat. Add carrot, turnip and leek; cook, stirring occasionally, until vegetables are crisp-tender. Remove vegetables from skillet; keep warm. Add scallops to empty skillet; cook, stirring frequently, until no longer translucent. Drain. Stir in pesto.
LADLE sauce onto four serving plates. Top with pasta, vegetables and scallop mixture.