"Ai no Tane" (愛の種, The Seeds of Love) is the unofficial debut single of Japanese pop idol group Morning Musume, released under a defunct independent label on November 3, 1997. It is sometimes called the "zeroth single"—"Morning Coffee" (モーニングコーヒー) being the "first single" and so on.

It was later included in many other Morning Musume releases: in their first official single "Morning Coffee"; their first album, First Time (ファーストタイム); and their first "Best of" compilation, Best! Morning Musume 1. An instrumental for this song was included in the bonus karaoke disc in the Early Single Box.

In 1997, Sharan Q organized a talent search competition named "Josei Rokku Vōkarisuto Ōdishon" (女性ロックヴォーカリストオーディション) under the show Asayan. After the competition, producer and Sharan Q vocalist Tsunku offered Yuko Nakazawa, Aya Ishiguro, Kaori Iida, Natsumi Abe, and Asuka Fukuda—five of the ten losers of the competition—the chance to be taken under his wing on one condition: to sell 50,000 copies of their debut single, which turned out to be "Ai no Tane." The girls agreed to the challenge and were named Morning Musume; thus, the recording of the song began.

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