Seed and fruit size affect soaking and physiological seed quality in Campomanesia adamantium?

Abstract

The size of fruits and seeds can affect the seed germination process and aspects related to the vigor of the seedlings formed. Our aim was to characterize fruit and seed biometrics, evaluate the effect of seed size on soaking and the effect of seed size and temperature on the germination and vigor of Campomanesia adamantium. The fruit was evaluated to determine longitudinal diameter, transverse diameter, fresh mass and empty, full and total seed quantities. The seeds were sorted into small, medium and large classes and then measured for length, width, thickness and mass. Seeds from each class were submitted to the germination test at 25 and 30 °C. The germination and vigor (first count, germination speed index, mean germination time and seedling length) data were evaluated by analysis of variance and a means test. Seeds from each size class were weighed repeatedly during soaking. The soaking data were fit to logistic and Peleg models and best fit curves with confidence bands were constructed to compare the effect of seed size. Fruit morphology showed high intraspecific variability. Germination was not affected by seed size or test temperature. Large seeds yielded taller seedlings while the 25 °C germination temperature produced the highest seedling growth rate. The small and medium seeds showed all three phases of the soaking process. Finally, soaking was initially slower for the large seeds than for the small and medium seeds.