By Rajendra Jadhav, Mayank Bhardwaj and Nigam Prusty MUMBAI (Reuters) -India banned wheat exports on Saturday days after saying it was targeting record shipments this year, as a scorching heat wave curtailed output and domestic prices hit a record high. The government said it would still allow exports backed by already issued letters of credit and to countries that request supplies “to meet their food security needs”. The move to ban overseas shipments was not in perpetuity and could be revised, senior government officials told a press conference. Global buyers were banking on supplies from th…