Im working in a Pineapple Plantation and I would like to explore more on other ways of inducing pineapple plants to flower and eventually to fruiting. In our Plantation we call it forcing or ethylation using Ethlylene gas plus adsorbent solution (water & China clay/activated carbon or ethephon plus urea.
Last edited by cameco; August 19th, 2010 at 05:49 PM.
Unsaturated gases like ethylene and acetylene in the form of smoke cause early flowering in pineapple. This can be achieved by applying acetylene saturated water or calcium carbide in the heart of the plant. About 50ml ethrel solution 10 ppm conc. in combination with 2% urea and 0.04% sodium carbonate can bring forth flowering. NAA@25 ppm also induces flowering.
To delay harvest by a few days (10 - 15 days), 300 ppm Planofix may be sprayed on the fruit just 60 to 70 days ahead of harvest.
To ripen the fruit earlier by about 10 - 15 days, 500 ppm of ethrel may be sprayed on the fruit about one month before normal harvest.
Staggering of harvesting almost throughout the year is possible by the following means
i. using different planting materials.
ii. planting suckers and slips at regular intervals from July-December and
iii. applying flower inducing chemicals at desired time as stated above
Pineapple flowering may be delayed or uneven, and it is highly desirable to attain uniform maturity and also to control the time of harvest in order to avoid overproduction in the peak periods. In 1874 in the Azores it was accidentally discovered that smoke would bring pineapple plants into bloom in 6 weeks. The realization that ethylene was the active ingredient in the smoke led to the development of other methods.
As far back as 1936, compressed acetylene gas, or a spray of calcium carbide solution (which generates acetylene) were employed to expedite uniform blooming. Some growers have merely deposited calcium carbide in the crown of each plant to be dissolved by rain. A more advanced method is the use of the hormone, a-naphthaleneacetic acid (ANA) or B naphylacetic acid (BNA) which induce formation of ethylene. In recent years, B-hydroxyethyl hydrazine (BOH) came into use. Treatment is given when the plants are 6 months old, 3 months before natural flowering time. The plants should have reached the 30 leaf stage at this age.
Spraying of a water solution of ANA on the developing fruit has increased fruit size in 'Smooth Cayenne' in Hawaii and Queensland. In West Malaysia, spraying 'Singapore Spanish' 6 weeks after flowering with Planofix, an ANA-based trade product, delayed fruit maturity, increased fruit size, weight and acidity. Similar results have been seen after hormone treatment of 'Cayenne Lisse' on the Ivory Coast.
Trials with 'Sugarloaf' in Ghana showed calcium carbide and BOH equally effective on 42-to 46-week-old plants, and Ethrel performed best on 35-to 38-week-old plants. 'Sugarloaf' seems to respond 10 days earlier than 'Red Spanish'.
Ethrel, or the more recently developed Ethephon, applied at the first sign of fruit ripening in a field will cause all the fruit to ripen simultaneously. It brings the ratoons into fruit quickly. There is a great saving in harvesting costs because it reduces the need for successive pickings.
Plants treated with naphthaleneacetic acid produce long, cylindrical, pointed fruits, maturing over an extended period of time, ripening first at the base while the apex is still unripe. Ethylene treatment results in a square shouldered, shorter fruit maturing over a shorter period and ripening more uniformly.