Influence of steckling transplanting date and steckling size on seed production of radish (Raphanus sativus L.) var. beeralu under Mid and Up Country Wet Zone of Sri Lanka

Field experiments were conducted at two locations representing Mid Country Wet Zone and Up Country Wet Zone to find out the impact of steckling transplanting time steckling size and location on seed production of Beeralu radish. Pre mature bolting occurred at Sita Eliya (WU2b) during both seasons restricting the imperative selection of true to type stecklings in root to seed method. Transplanting large (14-17 cm) and medium (11-13 cm) stecklings before mid July during Yala and before the end of December during Maha significantly increased (p<0.05) seed yield and quality over the small stecklings (7-10 cm) at Gannoruwa (WM2b). Seed yield and quality increased significantly (p<0.05) in Yala over Maha at Gannoruwa. Sita Eliya crop raised using the roots of Gannoruwa crops just for one transplanting date of Maha, confirmed the superiority of large and medium stecklings. Seed yield and quality were significantly higher (p<0.05) in Sita Eliya over Gannoruwa revealing the best conditions for seed production present under the low temperature conditions at Sita Eliya. Root production was impossible in Sita Eliya due to pre mature bolting occurred under low temperature conditions. This study reveal that transplanting true to type, more than 10 cm long stecklings, in Sita Eliya under poly tunnels or maintaining proper isolation to avoid out crossing is an appropriate method in quality seed production of Beeralu radish.