EFFECT OF BULB SIZE AND GROWTH REGULATORS ON GROWTH AND FLOWERING OF TUBEROSE CV. SINGLE

Abstract

The present study was conducted at the Horticulture farm of Shcr-c-Bangla Agricultural University, Shcr-c-Bangla Nagar, Dhaka, during the period from 01 May 2005 to 30 April 2006. The experiment was conducted to investigate the effect of bulb sizes i. e. srnal 1, medium and large ( 1.5-:?..0 , 2.1-2.5 and 2.6-3.0 cm in diameter respectively) and growth regulators i.e. Gibbcrellin (GA3) and Ethylene ( ethrel) on the growth and flowering of tuberose cv. Single. Bulb size had significant effect on plant height, height or the side shoot, number of leaves/plant (mother bulb), number of leaves/plant (side shoot), number of side shoots per plant, days to spike emergence, days to first flowering, duration of flowering. Bulb size had also significant effect on yield contributing characteristics. Large bulb was found to be superior to medium and small bulb. GA3 and ethrel signi licantly improved the plant characteristics relating to the growth and flowering of tuberose cv. Single. In general, influence of GA3 was more pronounced than ethrel in respect of all parameters except duration of flowering. Significant interaction was observed between bulb size and growth regulators treatments in respect of different parameters studied except number of side shoot/plant, duration of flowering and number of florets in 100 gm. The best results were obtained in the large bulb size when combined with GA3 followed by ethrel