Strategies to enable the use of silicon via fertirrigation to increase the efficiency of water use in the cultivation of maize and beans in the State of São Paulo

• Grant number: 21/12531-7
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2022
• End date: March 31, 2024
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Renato de Mello Prado
• Grantee: Renato de Mello Prado
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated researchers: Luiz Fabiano Palaretti ; Newton La Scala Júnior ; Priscila Lupino Gratão
• Associated scholarship(s): 23/02563-4 - Strategies to enable the use of silicon via fertigation to increase water use efficiency in corn and bean cultivation in the state of São Paulo, BP.TT

Abstract

Irrigated cultivation of annual crops such as maize and beans has expanded in recent years at the same time with water restriction due to climate change, so strategic research is essential to increase water use efficiency with sustainability. For this, balanced plant nutrition can contribute to increase the efficiency of water use, especially with the supply of silicon (Si) and potassium (K), but this synergy, especially in fertigated crops, is still unknown. Thus, it is important to have answers for the following hypotheses: i) there is an optimal and economical Si dose for fertigation and the Si content in the soil/solution and leaf suitable for its justified use, but it depends on the cultivated species; ii) Si is a multi-stress element to mitigate damage caused by moderate and severe water deficit associated with K deficiency stress (common in tropical soils) in maize and bean plants; iii) the optimal Si supply via fertigation associated with the optimal K can reduce the water requirement of both species while maintaining high productivity; iv) in addition, the two elements interfere in the decomposition of plant biomass, reducing CO2 emission. Thus, the treatments will consist of a 3x2x4 factorial, three water regimes: 80% (no deficit), 60% (moderate water deficit) and 40% (severe water deficit) of the soil water retention capacity; two potassium fertilization: deficiency (zero K) and sufficiency of K, and four doses of Si supplied via fertigation: 0; 4; 8 and 12 kg ha-1. To test these hypotheses, two experiments will be carried out with maize and beans, aiming to establish Si doses via fertigation and its synergy with K in three water regimes in physiological, biochemical, nutritional and environmental aspects to support a strategy for the efficient use of water in cropping system irrigated. (AU)