Effects of ‘flowering chemicals’ application on the development of inflorescence and fruit of pineapple. [Ananas comosus (L.) Merr. c.v. Phuket]

This comparative study of the effects of three different flowering chemicals, CaC2, ethephon, and NAA, on the development of inflorescence and fruit of pineapples c.v. Phuket was conducted at Amphoe Talang of Phuket Province, between December 2000 and September 2001. An experiment was arranged as a factorial design in RCB with 2 factors in 3 replications. In the first factor, there were CaC2 1 g/plant, ethephon 100 mg/l combenation with urea 1.5% 60 ml/plant, NAA 0.5 mg (1 ANAA tablet/plant), and the second factor was application period (one time and two times into the shoot tips of nine-month-old ground suckers). The results showed that the application of ethephon one time or two times led to faster floral development than in plants that received NAA or CaC2. In fact, the floral development with ethephon application was 5-7 days faster than that in NAA application, and 8-10 days faster than that in CaC2 application. Apical meristem differentiation took place 3 days after the application of ethephon, followed by complete development of the first floret and stamen within 42-43 days, anthesis within 45-46 days, and pistil within 48-49 days. Maturation of the egg was 5.7-6.3 days later than that of the pollen grains and 2.3-2.6 days after anthesis. In the treatment of NAA application once or twice, the development of the egg cell took a longer period