(Bloomberg) -- A top Indian fund manager is shunning lower-rated rupee corporate bonds until the impact of the world’s worst Covid-19 crisis on weaker borrowers is better understood.The level of stress in the economy especially for small- and medium-sized enterprises is still unclear after states locked down to curb the spread of a second virus wave from March, said Dhawal Dalal, who oversees $4.8 billion of debt assets at Edelweiss Mutual Fund. Dalal, who manages one of the best-performing debt