SHANGHAI: Shares on China's tech-heavy ChiNext board rallied for the second trading day on Tuesday as investors cheered the latest reform and relaxation of the bourse's listing and trading rules.

At the close, the blue-chip CSI300 index was up 0.13%, with its consumer staples sector up 1.85%, while utilities index was down 1.75%. The Shanghai Composite index was down 0.36% at 3,373.58.

ChiNext rose 0.63%, while the STAR50 index was down 1.58%.

Shares of a dozen companies surged for a second day after their debut on the ChiNext board on Monday, following a historic reform that allows Shenzhen to challenge Shanghai for tech listings.

Anhui Jinchun Nonwoven Co triggered intraday circuit breakers twice on Tuesday, as its shares soared by 76.9%. Shares of Shengyuan Environmental Protection Co, which debuted a day earlier, also surged 56.1% on Tuesday.

New ChiNext shares can now trade without daily cap for the first five trading days, and can trade up to 20% in sessions afterwards. It allowed shares to rise or fall up to 10% previously.

BOC International analysts wrote that a revamped ChiNext board will benefit brokerages who have listing projects on hand and new shares in the short term, and tech shares in the long run.

To add relief to the market, China said on Tuesday it agreed with the United States to continue pushing forward the implementation of the Phase 1 trade deal reached earlier this year during a call between top trade negotiators of the two countries.