Tokyo stocks were slightly lower Friday morning as sentiment was weighed by concerns over the impact of COVID-19 lockdowns in China on the global economy amid a lack of fresh trading cues. The 225-issue Nikkei Stock Average fell 68.20 points, or 0.25 percent, from Thursday to 26,820.37. The broader Topix index was down 5.83 points, or 0.31 percent, at 1,887.07. The Tokyo bourse on April 4 introduced the Prime, Standard and Growth markets to replace the four former trading segments — First Section, Second Section, Mothers and Jasdaq. On the top-tier Prime Market, decliners were led by transpor…