(a) Abu al-Gharif narrates from Sayyiduna Ali (may Allah be pleased with him) concerning the junub that he said: He should not recite the Qur'an, not even a single letter.
(b) Sayyiduna Ali (may Allah be pleased with him) said: Keep reciting the Qur'an as long as you are not (in a state of janabah).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 417