Physiological effect of nickel on nitrogen and antioxidant metabolism in sugarcane varieties.

• Grant number: 20/07263-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2020
• Effective date (End): July 31, 2021
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: André Rodrigues dos Reis
• Grantee: Mateus Vendramini Rampazzo
• Host Institution: Faculdade de Ciências e Engenharia. Universidade Estadual Paulista (UNESP). Campus de Tupã. Tupã , SP, Brazil

Abstract

Sugar cane (Saccharum officinarum) is extremely relevant for Brazilian economy. Brazil is the largest sugar producer and exporter and the second largest ethanol producer and exporter in the world. Nitrogen (N) metabolism is fundamental for sugarcane plants. Plant assimilate nitrogen into amino acids and proteins that participate in the metabolic processes in cells, playing a functional and structural role for plant growth. Nickel (Ni) is cofactor of urease enzyme and actively acts on the nitrogen and antioxidant metabolism of plants. Thus, this study aims to evaluate the physiological role of Ni on oxidative metabolism by quantifying reactive oxygen species and enzymes from the antioxidant system such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase. In addition, nitrogen metabolism enzymes will be evaluated such as nitrate reductase and urease and the concentration of urea in plant tissue in response toNi doses. Our hypothesis is that Ni can increase the activity of enzymes of nitrogen cycle in addition to increasing the antioxidative system in sugarcane varieties. Plants with greater efficiency in the use of nitrogen may present greater photosynthetic capacity, consequently will result in a greater accumulation of sucrose in different organs of the plant. Primary compounds such as nitrate, ammonia, total amino acids, sucrose and total sugars in plants treated with different Ni concentrations. There are no recommendations in the literature for Ni application in sugarcane. The present work can generate very important information for guide Ni recommendations based on physiological responses of sugarcane that they may possibly become future recommendations under field conditions.