国债期货开盘，30年期主力合约跌0.31%，10年期主力合约跌0.13%，5年期主力合约跌0.13%，2年期主力合约跌0.02%。

Core Viewpoint - The opening of government bond futures shows a decline across various maturities, indicating a bearish sentiment in the bond market [1] Group 1: Market Performance - The 30-year main contract decreased by 0.31% [1] - The 10-year main contract fell by 0.13% [1] - The 5-year main contract also dropped by 0.13% [1] - The 2-year main contract experienced a slight decline of 0.02% [1]