Nanoparticles as carrier systems in the treatment of soybean seeds aiming to soften the effects of drought stress

Abstract

Considering the impacts of climate change in recent decades, where drought is the most important, the soybean growth is under threat. In this context, the use of osmoprotective physiological functions such as trehalose may be an alternative to improve plant establishment and performance, promoting low environmental impact. The correct plant establishment is a trigger for a profitable production. Under drought stress conditions, the seed ability to generate a normal seedling is impaired, compromising the crop establishment and yield. Trehalose is a non-glucose reducing disaccharide that mediates the defense responses of seeds and plants against biotic and abiotic stresses such as drought. Given this, the exogenous application of trehalose in seed treatment can be an effective solution under non ideal water conditions for the increase of germination and seedling development. Given the complex dynamics of the agricultural environment, the application technology and formulation of exogenous trehalose used in plants and seeds should be efficient and cost effective. Nanocarrier particles provide protection against degradation and gradual release of bioactive substances. Thus, the objective of the project is the development of a commercial product for seed treatment, which is formulate by nanoparticles containing trehalose, and with this, to evaluate the soybean seed germination and seedling establishment under drought stress. The nanoparticles that are going to be in the product will be defined from preliminary analysis to evaluate the release performance and protection of trehalose and based on their behavior in the agricultural environment. To evaluate the physiological impact of the product, it will be used soybean seeds of the cultivar MG / BR 46 (Conquista) submitted to its seed treatment in different concentrations. The analysis will be: germination test, 50% germination average time, seedling dry matter length and mass and accelerated aging test. Under simulated drought stress conditions the seeds will be submitted to five concentrations of polyethylene glycol (PEG) and the parameters mentioned above will be evaluated. Under conditions of drought stress in sand (at 30 and 60% water retention capacity) will be measured the emergence and seedling emergence speed index, seedling length and seedling dry mass. The reinduction of desiccation tolerance, trehalose quantification, confirmation and anatomical studies of nanoparticle penetration in seed tissues will be characterized. The data will be submitted to analysis of variance with means compared by Tukey at 5% probability. Globally, the perspective for grain production is the lack of water for optimal seed germination at the time of sowing, and there is nothing on the market that can offer seed and seedling tolerance drought stress. The innovation of this present project has potential to be a solution on the establishment of crops under non-ideal water conditions, and thus, it can contribute strongly for the soybean production sustaining (future for other crops) and global food security. (AU)