Water Dynamics on Germinating Diaspores: Physiological Perspectives from Biophysical Measurements

POMONA: a multiplatform software for modeling seed physiology

Seed physiology is related to functional and metabolic traits of the seed-seedling transition. In this sense, modeling the kinetics, uniformity and capacity of a seed sample plays a central role in designing strategies for trade, food, and environmental security. Thus, POMONA is presented as an easy-to-use multiplatform software designed to bring several logistic and linearized models into a single package, allowing for convenient and fast assessment of seed germination and or longevity, even if the data has a non-Normal distribution. POMONA is implemented in JavaScript using the Quasar framework and can run in the Microsoft Windows operating system, GNU/Linux, and Android-powered mobile hardware or on a web server as a service. The capabilities of POMONA are showcased through a series of examples with diaspores of corn and soybean, evidencing its robustness, accuracy, and performance. POMONA can be the first step for the creation of an automatic multiplatform that will benefit laboratory users, including those focused on image analysis.

Acceleration in Germination Sensu stricto Plays a Central Role on Seedling Vigor in Post-Germination

An obvious relationship between germination sensu stricto and seedling development during post-germination has been considered, but not explained concerning vigor. Taking this into account, we used measurements of water dynamics in germinating seeds and seedling development to clarify that relationship. The biological model was soybean seeds, since it is the most relevant 'true seed' produced around world. Our findings suggest that the way energy is used (acceleration) and not its input (velocity) is the main aspect relating seed germination and seedling development, especially when considering vigor. However, velocity and acceleration can be complementary in analyses of seed physiology. Other measurements proposed here also have potential uses for testing vigor in seed lots, such as seedling vigor index and biological activity in the lot. Therefore, water dynamics in germinating seeds can be an interesting way for testing seed lots, because it is an easier, faster and cheaper method in relation to other non-destructive procedures.

Clues on an intraspecific communication system in seed-seedling transition

How much interactivity is in a seed-seedling transition system? We hypothesize that seed-seed, seed-seedling, and seedling-seedling interactions can drive the early plant development in artificial growth systems directly due to mutual stimulation phenomena. To test the hypothesis, we performed seed germination measurements, gene expression in germination sensu stricto, water dynamics in germinating seeds, and information theory. For a biological model, we used Solanum lycocarpum A. St.-Hil. seeds. This is a neotropical species with high intraspecific variability in the seed sample. Our findings demonstrate that the dynamic and transient seed-seedling transition system is influenced by the number of individuals (seed or seedling) in the artificial system. In addition, we also discuss that: (1) the information entropy enables the quantification of system disturbance relative to individuals at the same physiological stage (seed-seed or seedling-seedling), which may be determinant for embryo growth during germination and (2) the intraspecific communication in seed-seedling transition systems formed by germinating seeds has the potential to alter the expression pattern of key genes for embryo development. Therefore, the phenomenon of mutual stimulation during the germination process can be an important aspect of seed-seedling transition, especially in laboratory conditions.