Anatomical Analysis and Seed-Coat Imposed Dormancy in Parkia biglobosa

The effect of different treatments of breaking seed dormancy of Parkia biglobosa seeds were studied in this project work. The results of different treatments observed showed 88% for concentrated H2SO4, 80% for scarification (with scalpel) and 52% for dry heat while the untreated seed (control) is 40% germination. The speed of germination for some treated seeds are also observed to be greater than that of the untreated seeds with seeds treated with concentrated H2SO4 having the highest value of 32.35%, followed by mechanical scarification with 26.67%, heat with 13.97% and untreated seeds having 14.93%. The data collected when subjected to analysis of variance showed significant differences between the treatments, the leaves and seedling height performed better than the control (untreated seeds). Dry heat, mechanical scarification and concentrated H2SO4 were found to induce germination of the dormant seeds of Parkia biglobosa. These methods could be applied to raise seedlings of plant for field propagation and afforestation programme. The anatomical analysis of the seed coat shows that the seed coat is made up of 3 layers; the outer, the middle and the inner layer. Also shown in the seed coat microscopy are the sclereid, the macrosclereid, the brachysclereid and the light line. The range of dimension of some parameters like length and diameter of micropyle, depth and width of pleurogram and for the three layers of the seed coat was also observed in the anatomical structure of the seed coat of P. biglobosa.