Sorry I wasn't clear enough. By further try and false tests i managed to show dropdown menu creating a function outside of the component class but in the same js file. It worked as i wanted. Here is the code if anyone else need it

function DropDownMenu(rowData) {
console.log("DropDownMenu: " + rowData.planno);
return(
    <MDBDropdown size="sm">
        <MDBDropdownToggle caret color={((rowData.durumrenk === "danger") ? "danger" : ((rowData.durumrenk === "warning") ? "warning" : "primary"))} className="m-0 rounded-0">
            {rowData.planno}
        </MDBDropdownToggle>
        <MDBDropdownMenu basic color={((rowData.durumrenk === "danger") ? "danger" : ((rowData.durumrenk === "warning") ? "warning" : "primary"))}>
            <MDBDropdownItem><Link to={"/plandetay/"+rowData.planno+"/basvuru"}>Plan Düzenle</Link></MDBDropdownItem>
            <MDBDropdownItem><Link to={"/karar/"+rowData.planno+"/basvuru"}>Karar</Link></MDBDropdownItem>
            <MDBDropdownItem>Gözetim 1</MDBDropdownItem>
            <MDBDropdownItem><Link to={"/plandetay/"+rowData.planno+"/g1"}>Plan Düzenle</Link></MDBDropdownItem>
            <MDBDropdownItem><Link to={"/karar/"+rowData.planno+"/g1karar"}>Karar</Link></MDBDropdownItem>
        </MDBDropdownMenu>
    </MDBDropdown>
)

}

put this after

export default connect( mapStateToProps, mapDispatchToProps)(PlanList);

then update desired filed in row data like

    const rows = this.props.planlarMdb;
    const list = [];
    rows.forEach((element) => {
        const obj = Object.assign({}, element);
        obj.planno = DropDownMenu(element);
        list.push(obj);
    });

    let datatable = {columns: columns, rows: list}