Here, I made a little function for you, I checked it in my database (MAMP) and it works fine
use mySchema;
drop procedure if exists getParents;
DELIMITER $$
CREATE PROCEDURE getParents (in_ID int)
BEGIN
DROP TEMPORARY TABLE IF EXISTS results;
DROP TEMPORARY TABLE IF EXISTS temp2;
DROP TEMPORARY TABLE IF EXISTS temp1;
CREATE TEMPORARY TABLE temp1 AS
select distinct ID, parentID
from tasks
where parentID = in_ID;
create TEMPORARY table results AS
Select ID, parentID from temp1;
WHILE (select count(*) from temp1) DO
create TEMPORARY table temp2 as
select distinct ID, parentID
from tasks
where parentID in (select ID from temp1);
insert into results select ID, parentID from temp2;
drop TEMPORARY table if exists temp1;
create TEMPORARY table temp1 AS
select ID, parentID from temp2;
drop TEMPORARY table if exists temp2;
END WHILE;
select * from results;
DROP TEMPORARY TABLE IF EXISTS results;
DROP TEMPORARY TABLE IF EXISTS temp1;
END $$
DELIMITER ;
this code will return all parents to any depth.
you can obviously add any additional fields to the results
use it like this
call getParents(9148)
for example