BIOFERTILIZER COMPOSED OF BACTERIA AND NANOSILICA TO MITIGATE HEAT STRESS IN RICE AND BEAN CROPS

Abstract

Food security faces a complex challenge due to the ongoing loss of soil fertility and the imminent danger of climate change. Sustainable solutions are urgent to preserve natural resources and mitigate the negative impacts of global warming on agricultural production. In this way, biofertilizers have emerged as an alternative to chemical fertilizers and pesticides in agriculture, as they do not pose risks to the environment/health of living beings and are economically advantageous. The demand for these biological products has been growing exponentially worldwide, especially in Brazil, where agriculture depends on imported synthetic inputs, with high costs for the producer. Despite their advantages, microbial biofertilizers can present problems such as inconsistency and ineffectiveness due to the field's various environmental factors and interactions. Therefore, it is necessary to explore different technologies to make them more stable and effective. Rice and beans are rich in nutrients and play an essential role in the Brazilian and other countries' diets, with Brazil being one of the largest bean producers in the world. However, these crops are susceptible to climate variations, reducing agricultural production when temperatures increase. Silica nanoparticles can be used in the formulation of biofertilizers to increase the efficiency of bacteria in promoting plant growth and tolerance to heat stress. In this context, the proposed project aims to formulate an innovative biofertilizer composed of bacteria and silica nanoparticles to promote plant growth and reduce heat stress in rice and bean crops.The bacteria, which belong to the Laboratory of Biomolecules and Microbiology's collection at the Federal University of São Carlos - UFSCar, were previously isolated from the Cerrado biome and demonstrated in vitro capacity for nitrogen fixation, phosphate solubilization, and production of indoleacetic acid (IAA). The innovation of the proposed biofertilizer is the application of silica nanoparticles to increase the stability and effectiveness of bacteria that promote plant growth and make plants more tolerant in conditions of heat stress, being a product with significant commercial potential, as it presents itself as an ecological, economical and efficient solution for nutrition and thermal protection for rice and bean crops, which constitute the food base of the Brazilian population and have low tolerance to thermal fluctuations. (AU)