Laser irradiation is considered a new technology in agriculture; however, the success of irradiation depends on the selection of precise parameters for the light source and exposure. In this study, the impact of laser stimulation on germination and the occurrence of mycoflora in soybean seeds was assessed. The following factors were considered: (1) irradiation using blue and red coherent lights, (2) irradiation of seeds only (a), use of Bradyrhzobium japonicum vaccine only (b), and irradiation of the seeds plus the Bradyrhzobium japonicum vaccine (c). The germination index, seedling weight and seeds infected by fungus were determined. It was found that the laser treatment of seeds increased germination and seedling weight. Laser irradiation affected the abundance of species Phoma glomerata, Botrytis cinerea, Rhizopus nigricans and Gliocladium roseum. The use of blue laser (LB—514 nm) reduced the number of the non-pathogenic species, R. nigricans and G. roseum.
Pre-sowing laser light stimulation is a method commonly used to increase the productivity of legume species. However, it has not been proved that single-laser light stimulation is a more effective technique for enhancing plant productivity and seed yield quality than using different laser lights in sequence, by which means synergistic relations are produced. A two-year, single-factor field experiment was performed in order to test selected combinations of light stimulation of soybean seeds, the effectiveness of which would be expressed as increased plant yield and improved quality parameters. Pre-sowing light stimulation of soybean seeds was shown to significantly influence the morphological traits of the plants. It significantly increased pod number, pod weight, seed number, and seed weight compared to the control. Coherent laser light stimulation of soybean seeds with a helium–neon laser and with an argon laser increased soybean yields by 30% on average compared to the control. The ratio of the yield from the main shoot to the yield from the lateral branches in this treatment was 40:60, indicating that pre-sowing stimulation of seeds had a significant and positive effect by increasing the yield of the lateral branches relative to the control. Stimulation of seeds (3 × 3 s) with a helium–neon laser significantly increased protein content in soybean seeds, on average by 11% compared to the control. A longer duration of pre-sowing stimulation of seeds (3 × 9 s) resulted in a significant increase in crude fat content in the seeds by an average of 5% compared to the control. The use of physical light stimulation on soybean seeds is a promising solution for increasing soybean yields.
The laser stimulation of seeds is regarded as a modern method of seed enhancement. Our study evaluated the productivity and health of soybean plants resulting from the coherent irradiation of seeds and irradiation of an arbuscular mycorrhizal fungi (AMF) inoculum. The two-factor pot experiment took into account (1) the type of irradiated biological material (seeds, AMF inoculum, and seeds and inoculum) and (2) the means of irradiation (red laser—LR, blue laser—LB, red and blue laser—LR + LB, and control). Seed weight per plant, pod number per plant, root weight, the Fv/Fm fluorescence parameters, and the health status of the aboveground and underground parts of the plants were assessed. Stimulation with a laser light was shown to have a positive effect on the productivity and health of soybean plants. Significantly better effects can be obtained by stimulating the seeds alone. The stimulation of seeds treated with AMF inoculum slightly reduced the productivity of the plants. However, with regards to the conditions of plants, the treatment of seeds with AMF inoculum and laser irradiation was shown to reduce the incidence of Septoria brown spots.
1 December 2020 in IOP Conference Series: Earth and Environmental Science
The key factor for sustainable development is the integration of sensitive methods for early detection of environmental risk factors for nutritional health with efficient primary prevention against contamination of the food chains as well as deficiency of biologically active trace elements in the human diet. Proper algorithms of laser photostimulation are recommended both for more efficient biological treatment of wastewater and also for a proper amount of essential elements in cultivated plants supplemented by other modern biotechnology for multiplication e.g. vegetables. Laser biotechnology is also recommended for better reclamation followed by enhancement of biomass and bioenergy production in different regions of the world as a contribution to sustainable development and the creation of many green jobs. This eco-innovation supplemented with the complementary biotechnologies e.g. reclamation of semiarid areas, modern apiculture integrated with the cultivation of medical plants, cultivation of algae, aquaculture, energy plantations, reforestation and protection of biodiversity could contribute to better adaptation to climate change and situation connected with COVID-19 pandemic and risk of worsening human health, malnutrition, and hunger.