Monitoring of Spring Phenology and Pollen Studies in Delonix regia (Boj. Ex Hook.) Raf

A study was conducted to reveal the spring phenology and pollen studies in Delonix regia in the College of Forestry, Allahabad Agricultural Institute- (Deemed University) Allahabad, U.P. The study revealed that the synchronous flowering of Delonix regia started during first week of April and ended towards last week of June. Full blooming period was observed from last week of April to 2^nd week of June. Microscopic studies revealed circular pollen grains with a three germ pore. The maximum anthesis averagewas observed between 06:30 a.m. to 10:30 to a.m. Maximum anther dehiscence was recorded between 10:00 a.m. to 11:00 a.m. Total number of stamens per flower was ten with average size of 4.9 cmand number of Gynoceium was one with average maximum size of 5.9 cm. Main flower visitors identified on Delonix regia were Nectarinia sp, Merops orientalis and Dicrurus macrocercus. Pollen grains were yellow in colour, circular and 3-colporate. In-vitro pollen germination test indicated that in 20 per cent sucrose solution gave maximum germination (78.94) per cent after 12 hours of pollen dispersal.