According to Official Guinness Records,
The most TV talk shows hosted by the same presenter is 10,000 episodes by Tetsuko Kuroyanagi (Japan) on her show "Tetsuko no Heya" (Tetsuko's Room) as of 27 May 2015. The talk show has been broadcast daily by TV Asahi (Japan) since 2 February 1976. Erika Ogawa from Guinness World Records appeared on the 10,000th episode of the show and handed Ms. Kuroyanagi the official certificate to commemorate her achievement.
For a complete list of 2015 records, please visit 2015 Guinness Records in Japan.