The phenology of flowering in Citrullus lanatus (Thumb.) Mansf. in southwestern Nigeria
An optimal fruit set in water-melon is highly dependent on the appropriate timing of pollination. This study was conducted in two cropping seasons, to determine the most suitable and appropriate time of pollination of water- melon. Water-melon was sown at the rate of 2 seeds per hole at a spacing of 2 x 2 m. At floral induction, flower buds were tagged to monitor the number of male to female flower ratio, sequence of flower development and pollen rating from 5.00 to 19.00 hrs. The result of the study showed that, there were 50 - 100 males to 1 female flower. Flowers opened at a relatively fast rate in the morning till mid-day and closed gradually in the evening. Also, the pollen rating was highest between 6.00 and 11.00 hrs and subsequently declined steadily as the flower closed up at 18.00 hrs. The best period for pollination to obtain optimum fruit set in water-melon was therefore at stages 3 - 6 in this study which fell within 7.00 and 12.00 hrs.
Keywords: Floral development, phenology, pollen rating, water-melon