Germination and seedling development in Pistia stratiotes L.

This study aimed to describe the post-seminal development, evaluate how the available water, light and temperature influence seed germination and to describe the vegetative propagation by selecting one of the collected plants of Pistia stratiotes. The plant material was collected in a tributary of the Rio Igaraí§u, Parnaí­ba, Piauí­ State, Brazil. A botanical description of the species was made using individuals collected in the study area. For the germination tests, a total of 1400 seeds were harvested and three experiments were conducted, varying the amount of available water, light and temperature. The results showed that the highest percentage of germination is occurred with seeds pre-washed with distilled water, sown on filter paper with abundant water (enough to form a sheet of water) and exposed to alternating light at an average temperature of 37°C. Germination began on the fourth day after sowing, marked by the appearance of the cataphyll. After 22 days, the seedling stage was completed. Vegetative propagation of this species is efficient and fast. In 50 days, a total of 134 new vegetative shoots were recorded in just one individual. The results showed that the germination rate is related to the amount of light and temperature.