Flowering, Floral Biology and Pollination in Coconut
In a bearing palm, every leaf axil can produce a Spadix or infloresence which under normal conditions various from 12 to 15 annually. : :The inflorescence develops within a strong, tough, pointed toubje sheath called spathe, which after full development splits from top to bottom and releases the inflorescences. This usually occurs from 15 to 90 days after the first appeearence of its tip in the leaf axil. The primordis of the inflorescence begin to form in the leaf axil about 32 months before the opening of the spath.
Coconut Palmis monecious and produces several hundred male and few female flowers on the same infforescance, if bears about 30-35 apikelets each having about 250-300 male flowers at its top and one or few female flowers at the base. In general the no. of female flowers/inflorescence varied from 10-50.
The male flowers has six thin yellow parianth leaves surrounding, six stamens and three nectors glands at the center. When the male flower open, the anthers are split longitudinally releasing large quantities of yellow pollens for about 24 hours and then drop after pollen discharge or anthesis will continue for about 18-20 days (male phase). The pollen usually remain viable for about 2-9 days after it is discharge.
The female flower or ‘button’ is globose and consists of six floshy perianth leaves surrounding the pistil. The pistil is white and has three ridges which converge at the tip. When the flower is developed, these ridges split open exposing the sticky surface of the stigma which is extended as three erect teeth. Normally, .the opening of female flower commences by the 21st day, but during the summer months, the flowers may open even from the 19th day onwards. The female phase lasts for 4-7 days.
Generally the dwarf palms are considered autogmous (self pollination), the tall allogamous (cross pollinationg) and the hybrid and a few dwarf type particularly the green ones capable of uniting both the types however, overlapping of phases of two successive inflorescance is a characteristic conditioned by the interaction between go no type and environment.
Both wind and insects are considered to be the main pollinating agents, among them baees are important. Besides bees other pollinating insects are ousefly, wapps and beetles. After pollination unfertilized flowers turn brown and drop down A number of fertilized flowers also fail to develop properly and they drop.down generally not more than 25 to 40% female flowers reach maturity (Thampan, 1982).
Stedding of buttons and immature nuts and production of barren, nuts.