RESIDUAL IMPACT OF SILICON FERTIGATION ON THE SPROUTING AND PRODUCTIVITY OF SUGARCANE SOQUEIRA GROWN WITH AND WITHOUT WATER DEFICIT

• Grant number: 23/11782-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2024
• End date: December 31, 2024
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Renato de Mello Prado
• Grantee: Alan Moretto Ferreira de Aguiar
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

The use of irrigation associated with the use of sugarcane harvesting without burning the straw or the raw cane system are important agricultural practices to enhance the productivity and sustainability of the cultivation of this crop. However, in the raw cane system, there is a concern about a decrease in stump sprouting and also the water deficit that may reflect on the initial growth of the crop. For the growth of sugar cane there are several phenological components such as the number of tillers, the height of the stalks, the density of the stalks, which are under genetic control, but which are subject to environmental influences, especially nutritional ones. A sustainable approach to enhance sprouting in ratoons cultivated in an irrigated system with or without water deficit would be the use of soluble silicon, but research is lacking. In this sense, this study aims to investigate the residual impact of silicon (Si) applied via fertirrigation on plant cane and its effects on the sprouting of the first sugarcane stump. For this, an experiment will be carried out in the experimental area of the Universidade Estadual Paulista (UNESP), Jaboticabal, São Paulo. The study will be carried out in a Slip-Block experimental design with a 2 x 2 factorial, involving two levels of water retention in the soil (70% and 35% of the retention capacity) and two silicon application conditions (0 mmol and 1, 8 mmol) in 5 blocks. The experimental evaluations comprise the analysis of the number, diameter and height of the plants, electrolyte leakagecells to evaluate the integrity of the membranes, content of chlorophyll, carotenoids and pheophytins, photosystem II quantum efficiency, ascorbic acid content, phenolic compounds,amino acids and total sugars. In addition, dry mass production and the concentration and accumulation of carbon, nitrogen, phosphorus and silicon, stoichiometric C, N and P ratios and nutrient use efficiency will be evaluated. The study is expected to reveal whether silicon applied via fertirrigation in previous cycles contributes to the reduction of electrolyte leakage and activation of stress mitigation mechanisms under conditions of adequate irrigation and deficit, improving better quantum efficiency of photosystem II and homeostatic balance of nutrients, reflecting in sugarcane regrowth. This study addresses relevant aspects for optimizing sugarcane production, with possible implications for stress resistance and nutrient utilization. Understanding the residual effects of silicon can contribute to more sustainable and effective agricultural practices, in addition to providing subsidies for the proper management of sugarcane cultivation in environments with water deficit.