\begin{tikzpicture}[
   edge from parent fork down,
   auto
]
\tikzset{ 
   treenode/.style={align=center}, 
   root/.style={treenode, inner sep=10pt, text width = 30mm, font=\large}, 
   1/.style={treenode, inner sep= 10pt, text width = 25mm, font=\large}, 
   2/.style={treenode, inner sep= 10pt, text width = 17mm, font=\large},
   3/.style={treenode, inner sep= 10pt, text width = 12mm, font=\large}, 
   4/.style={treenode, inner sep= 10pt, text width = 8mm, font=\large},   
   %level/.style={level distance=1.5cm},
   level 1/.style = {sibling distance=7cm, level distance=2cm}, 
   level 2/.style = {sibling distance=3cm, level distance=2cm}, 
   level 3/.style = {sibling distance=3cm, level distance=2cm} 
}  
%[level distance=1.3cm,
%   level 1/.style={sibling distance=3cm, level distance=1cm},
%   level 2/.style={sibling distance=1.5cm, level distance=0.8cm}]
%   level /.style={sibling distance=1.5cm, level distance=0.8cm}]
\node[root, draw](tree){$1.\;\;2\;\;3.1.$}
   child {node[1,draw] {$4.1.-4.3.$}
   child {node[2,draw] {$4.4.-4.5.$}}
   child {node[2,draw] {$4.6.$}}
}
child {node[1, draw] {$3.2.-3.3.$}
   child {node[2,draw] {$5.1.-5.5.$}
   child {node[3,draw] {$5.6.$}
   child {node[4,draw] {$6.$}}}
   child {node[3,draw] {$5.7.$}}
   child {node[3,draw] {$5.8.$}}
   child {node[3,draw] {$5.9.$}}
   child {node[3,draw] {$5.10.$}}}
};
\end{tikzpicture}
%!tikz source end