Bring a medium saucepan of water to a boil. Add the daikon and cook over high heat just until tender, about 5 minutes; drain. Rinse out the saucepan and add the vinegar, sugar, curry powder and 1/2 teaspoon of salt. Tie the coriander seeds, star anise, cinnamon stick and peppercorns in a small piece of cheesecloth, add them to the saucepan and bring the mixture to a simmer, stirring just until the sugar is dissolved. Cover and let the mixture steep for 15 minutes. Transfer the pickling liquid to a large heatproof bowl, add the blanched daikon and let stand at room temperature until cool, or refrigerate for up to 6 hours.