The main drivers of export growth in October included petroleum products, electronics, gems and jewellery, chemicals, and engineering goods. By Shivangi Acharya and Manoj Kumar NEW DELHI, Nov 13 (Reuters) - India's merchandise trade deficit widened to a one-year high of $39.88 billion in October, exceeding forecasts as festive-season. Exports and imports both recorded strong growth during the month, although the increase in imports outpaced export growth in absolute.