\documentclass[ngerman]{scrartcl}

\usepackage{babel}
\usepackage[T1]{fontenc}
%\usepackage{libertine}

\usepackage{luaotfload}

      \DeclareFontFamily{T1}{libertine}{}
      \DeclareFontShape{T1}{libertine}{m}{n}{<-> "fxlr:+liga"}{}
      \DeclareFontShape{T1}{libertine}{m}{it}{<-> "fxlri:+liga"}{}
      \DeclareFontShape{T1}{libertine}{m}{sl}{<-> "fxlro:+liga"}{}
      \DeclareFontShape{T1}{libertine}{b}{n}{<-> "fxlb:+liga"}{}
      \DeclareFontShape{T1}{libertine}{b}{it}{<-> "fxlbi:+liga"}{}
      \DeclareFontShape{T1}{libertine}{b}{sl}{<-> "fxlbo:+liga"}{}
      \DeclareFontShape{T1}{libertine}{m}{sc}{<-> "fxlr:+liga:+smcp"}{}
      \DeclareFontShape{T1}{libertine}{b}{sc}{<-> "fxlb:+liga:+smcp"}{}
      \DeclareFontShape{T1}{libertine}{m}{ic}{<-> "fxlric:+liga:+smcp"}{}
      \DeclareFontShape{T1}{libertine}{b}{ic}{<-> "fxlbic:+liga:+smcp"}{}
      \DeclareFontShape{T1}{libertine}{bx}{n}{<->ssub * libertine/b/n}{}
      \DeclareFontShape{T1}{libertine}{bx}{it}{<->ssub * libertine/b/it}{}
      \DeclareFontShape{T1}{libertine}{bx}{sl}{<->ssub * libertine/b/sl}{}
      \DeclareFontShape{T1}{libertine}{bx}{sc}{<->ssub * libertine/b/sc}{}
      \DeclareFontShape{T1}{libertine}{bx}{ic}{<->ssub * libertine/b/ic}{}
      \def\libertine{\fontfamily{libertine}\selectfont}
      \renewcommand\rmdefault{libertine}%

\begin{document}


Text \par
 \textbf{Text} \par


\end{document}