FRANKFURT (Reuters) - Volkswagen overtook software maker SAP on Wednesday as the most valuable company in Germany’s blue-chip DAX index, as investors warm to the carmaker’s plans to take on Tesla. Volkswagen shares rose as much as 12%, giving the company a market valuation of more than 136 billion euros ($162 billion), compared with SAP’s 127 billion. Volkswagen shares have gained 47% year-to-date, supported by a raft of announcements on its electric vehicle expansion strategy, which culminated in a “Power Day” this week including plans to build six gigafactories in Europe by 2030. Chief Executive Herbert Diess said on Tuesday he thought Volkswagen, the world’s second-largest carmaker after Toyota, was worth 200 billion euros, still a far cry from Tesla’s $650 billion market value. ($1 = 0.8401 euros)