Europe's main stock markets rose at the start of trading on Tuesday, with London's benchmark FTSE 100 index of leading companies up 0.20 percent at 5,853.52 points. Elsewhere, Frankfurt's DAX 30 gained 0.21 percent to 7,306.33 points and in Paris the CAC 40 added 0.41 percent to 3,420.38. Asian equities traded mixed on Tuesday, with concerns over Europe's debt crisis overshadowing strong gains in Shanghai and Hong Kong. With the corporate earnings season coming up, dealers were taking a cautious approach, while a cut in growth forecasts for the regional and world economy by the International Monetary Fund (IMF) also weighed on investor sentiment. the