Not sure about vegetable but there is a fruit called Quince. :)
Quince, Quenepa, Quandong
quince
A quince is a fruit that's like an apple/pear.
Quince, and Victoria plum.
Some fruits beginning with the letter Q:QuamashQuandongQueensland nutQuenepaQuince, a sour, apple like fruit, quail/quail egg.Qumquat (Kumquat)
zuchini (sp?) - vegetableZucchini
Quince is a fruit that looks like a pear. It is bright golden-yellow when mature.
No vegetable starts with qux. The leaf and the root of the ullucus are an edible vegetable. As for q, there is quinoa, which is a grain, so I suppose that might be classed as a vegetable.
Quince quinientos quince milesimas
with a quince preserver
Quince is fourteen in Spanish.