Seed respiration is a key metabolic process linked to physiological status. Q2 respiration analysis enables detailed profiling of individual seeds, and combined with multispectral imaging, allows to explore seed-to-seed relationships between respiration and spectral or morphological traits. Thus,the study aims to investigate the relationship between the respiration profiles of individual soybean seeds and their morphological and spectral characteristics, using single-seed respiration analysis and multispectral imaging. Multispectral images were captured from 1,808 seeds using the VideometerLab system, from which 75 features were extracted. The seeds were placed in vials with 0.4% (w/v) agar to induce germination and sealed with caps containing a fluorescent polymer dot. The Q2 analyzer, tracked the oxygen consumption of each seed during germination. Both the VideometerLab and Q2 analyzer data were categorized through hierarchical clustering, and a subpopulation of seeds was selected from three categories of respiration profiles due to computational limitations. The association between respiration patterns and biometric features was analyzed using contingency tables and entropy analysis. The results revealed significant differences in respiration patterns, particularly in autofluorescence excitation-emission at 365/600, 430/700, 450/700 and 470/700 nm, as well as in reflectance at 365, 690 and 405 nm. Notably, 75% of seeds with similar respiration profiles were grouped based on similarities in their biometric characteristics, suggesting a relationship between respiration patterns and biometric features. Additionally, patterns of certain biometric traits indicated that different combinations can lead to similar respiration profiles, highlighting the complexity of evaluating this association.

Many common agronomic practices affect weed seed dormancy and germination by influencing the microenvironmental and edaphic conditions surrounding seeds in soil. Factors such as light penetration, soil water content, soil fertility, and temperature are modified by tillage, planting, harvesting, and other production practices, resulting in enhanced or depressed weed seed germination. Changes in these environmental factors may also indirectly lead to alterations in phytohormone concentrations during seed development, which can subsequently affect dormancy status of the mature seed. Integrated approaches that place priority on depleting weed seed banks through interfering with dormancy or germination requirements have strong potential to enhance weed management aspects of agricultural systems.

The seeds of Schinus molle are referred to as displaying physical dormancy because of their water-impermeable endocarp. Therefore, this work aimed to evaluate the germination of S. molle seeds as related to environmental conditions, scarification, storage time and seed anatomy. Various experiments were conducted to test the alleviation of dormancy in newly collected and stored seeds. Acid-scarified seeds incubated under continuous light at 25°C showed greatest vigour and germination. The separation of seeds by specific gravity revealed a higher germination percentage for those seeds that sank. In addition, dry storage alleviated dormancy with a remarkable increase in the various germination parameters. Overall, germination traits decreased after prolonged storage, but even after 12 months the means for germination parameters for stored seeds were still higher than those of newly collected ones. S. molle seeds remain attached to parts of the fruit mesocarp and endocarp. The mesocarp contains several layers of parenchyma showing secretory cavities. The endocarp consists of three layers of sclereids surrounding the embryo. Acid scarification strongly changed the structure of the external layers in the mesocarp, digesting parenchyma cells and removing the contents from both parenchyma cells and the secretory cavities; this improved water uptake during imbibition, which occurred only at the carpellary hilar slit. In conclusion, S. molle seeds are positively photoblastic and show physiological dormancy which can be alleviated by acid scarification and dry storage. Seeds can be stored for over 12 months without significant losses in germination parameters compared to newly collected seeds.

A critical analysis of different criteria used in investigating seed diversity was made. It is concluded that the most promising way to understand the evolution of seeds is to study not only their morphological features, as used by most workers in the field, but also the physiological diversity of seeds in connection with the taxonomic system of plants, together with their ecological and geographical peculiarities.