Propagation of papaya (Carica papaya L.) cv. Holland in tissue culture

Abstract

Papaya (Carica papaya L.) is an important economical fruit plants in Thailand. Papaya is trioecious with three basic sex forms: female, male and hermaphrodite on separate plants. The fruit developed from hermaphrodite flower contains more flesh, less seed, and longer fruit shape (pyriform) than female flower. Therefore, only hermaphrodite plant results in a more commercial value for the fruit production. Normally, Papaya from seed provided 70 % hermaphrodite and 30 % of females. In papaya planting, 2 - 3 seedlings are planted per hole to obtain a hermaphrodite. A lot of papaya seedlings were used to grow in the field. Propagation by tissue culture tends to produce the original varieties and large quantities papaya trees in a short time. The purpose of this research was to effect of NAA and BA with MS media on tissue culture of papaya a cv. Holland. Shoot tip was cultivated on MS medium supplemented with 0-0.2 mg/l (NAA) and 0 - 0.45 mg/l (BA) in vitro condition at 25 ± 2 oC with light 16 hrs./day for 60 days. The results showed that the MS media with NAA + BA no Influence on the number of shoots and shoot length (P > 0.05). But have significantly in the number of roots, root length and number of leave (P < 0.01). MS media with NAA 0.10 mg/L + BA 0.45 mg/Lgave the highest number of shoots (4.14 + 0.69 shoots) and NAA 0.10 mg/L + BA 0.15 mg/L gave the highest number of roots (8.71 + 2.21).