Relationship between the chlorophyll fluorescence during germination and the physiological potential of soybean seeds

Abstract

Chlorophyll fluorescence imaging is an effective method for monitoring parameters related to the physiological potential of seeds, and represents a promising tool to reduce the subjectivity of traditional analytical tests as well as the low reproducibility among laboratories. During soybean seed germination, the cotyledons have a key role in the development of the embryonic axis since they contain the nutrients and also due to their photosynthetic activity. This project aims to evaluate the activity of soybean cotyledons during germination by monitoring chlorophyll fluorescence in order to establish a relationship with the differences in seed vigor observed in traditional vigor tests (first count of germination test, saturated salt accelerated aging - SSAA, seedling emergence and emergency speed index -ESI). Two soybean cultivars will be investigated, each represented by seed lots with different physiological potentials. The study will be conducted in two experimental periods, with an interval of six months. The chlorophyll fluorescence signals will be measured using the SeedReporter Camera Spectral & Color equipment, granted in the Young Investigator Project (Fapesp Process nº 2017/15220-7). Initially, chlorophyll fluorescence measurements will be carried out to identify green seeds, which may affect the seed vigor. Then, the chlorophyll fluorescence and photosynthetic efficiency of cotyledons will be monitored during germination. The main scientific contribution expected with the present research proposal is the development of markers based on chlorophyll fluorescence imaging during germination to predict soybean seed vigor in a fast and objective way. (AU)