# Soybean Germination Response to Algae Extract and a Static Magnetic Field Treatment
## 1 Introduction
Pre-treatment of seeds before sowing with magnetic fields is considered eco-friendly technology, safe for the environment and plants, since the field only affects seeds to stimulate their germination, which favors better dynamic emergence and good growth of seedlings [23; 27; 36]. The results of these treatments are greater plant vigor and a higher yield. Examples of SMF impact on soybean seeds are presented in Table 2. \begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Magnetic Induction [mT\({}_{7}\) Millitesla]** & **Time of Exposure** & **Effects** & **Reference** \\ \hline
72–128 & 13–27 min & 46\% increase in yield at an optimal magnetic induction of 100 mT for 25 min as compared to the control **(F)** & [37] \\ \hline
2.9–4.6 & 2.2; 6.6; 19.8 s & shoot formation—the highest for 2.2 s (87.0\%) and 6.6 s to the control (61.9\%); root formation—the highest for 2.2 s (26.1\%) and 6.6 s (35.9\%) as compared to the control (14.3\%); fresh weight—significant increase for 6.6 s as compared to the control; chlorophyll \(a\) and chlorophyll _b_—the highest for 2.2 s **(L)** & [38] \\ \hline
50; 100; 150; 200; 250; 300 & 30; 60; 90 min & improvement in germination speed (5–42\%), seedling length (4–73\%), fresh weight (9–53\%), dry weight (5–16\%) and vigor indices I (germination percentage - seedling length) (3–88\%) and II (germination percentage - seedling dry weight) (4–27\%) as compared to the control; the best results—magnetic induction of 200 mT and 150 mT and time 60 min; leaf area, and leaf fresh weight—maximum enhancement (more than twofold) in 1-month-old plants; polyphasic chlorophyll \(a\) fluorescence transients from SMF treated plants—higher fluorescence yield at the J–I–P phase **(L)** & [39] \\ \hline
150; 200 & 60 min & enhanced production of reactive oxygen species mediated by cell wall peroxidase; decrease in ascorbic acid content, superoxide dismutase, and ascorbate peroxidase activity in hypocotyl as compared to the control **(L)** & [40] \\ \hline
100; 150; 200 & 0.5 min & 100 and 150 mT—increaseand fresh and dry biomass—not affected **(L,F)** & [41] \\ \hline
2.9–4.6 & 2.2; 19.8 s & shoot formation—the highest for 2.2 s (94.3\%) and 19.8 s (78.2\%) as compared to the control (28.6\%); root formation—the highest for 2.2 s (4.76\%) and 19.8 s (47.2\%) as compared to the control (54.5\%); increase in fresh weights of plantlets regenerated from treated explants as compared to the control; chlorophyll \(a\), chlorophyll \(b\) and total chlorophyll contents—increase for 2.2 s by 21\%, 13\%, and 18\% respectively as compared to the control; peroxidase activity and the total RNA concentration—significant increase for both times as compared to the control **(L)** & [42] \\ \hline
200 & 60 min & increase in a number of root nodules, fresh weight, biomass accumulation, and photosynthetic performance under both non-saline and saline conditions as compared to the control; polyphasic chlorophyll \(a\) fluorescence—higher fluorescence yield at J–I–P phase; higher nitrate reductase activity, photosynthetic pigments and net rate of photosynthesis; increase in leghemoglobin content and hemochrome content in root nodules as compared to the control **(L)** & [43] \\ \hline
200 & 60 min & SMF alleviates salinity stress in early seedlings stage; increase in \(\alpha\)-amylase and protease activities and levels of superoxide radical and hydrogen peroxide as compared to the control **(L)** & [44] \\ \hline
200 & 60 min & increase in plant height, leaf area, biomass accumulation and hemochrome content in the root nodules; improvement in the PSII efficiency and rate of photosynthesis both in the presence of solar UV components as well as under exclusion of solar UV as compared to the control **(L)** & [45] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The effects of SMF on soybean seeds. There are only a few studies about simultaneous use of macroalgal extracts and SMF on early stages of soybean development.