Improving soil health and reducing water stress in semi-arid cotton production system with cover crops and compost

• Grant number: 24/23243-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: June 10, 2025
• End date: June 09, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Fábio Rafael Echer
• Grantee: Gustavo Ricardo Aguiar Silva
• Supervisor: Glen Lorin Ritchie
• Host Institution: Faculdade de Ciências Agrárias. Universidade do Oeste Paulista (UNOESTE). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil
• Institution abroad: Texas Tech University (TTU), United States
• Associated to the scholarship: 23/03112-6 - Water availability of a sandy soil and its impacts on the physiology, productivity and quality of the cotton under crop rotation system with different carbon accumulation potentials in the soil, BP.DR

Abstract

Water deficit is one of the most limiting factors in crop yield, and to reduce this negative effect of prolonged drought, strategies to improve water retention during the season are essential to increase crop yield. Cover crops can improve water soil water content, as well as cattle manure. The objective of the study will be to evaluate the effect of cover crops and cattle manure application on total soil organic carbon and water content, cotton development and fiber yield. The experiment will be conducted in the field at Texas Tech University's New Deal experimental station in New Deal - Texas. The treatments consist of the exposure or not of cotton to drought, cover crops and application of cattle manure: 1) Cattle manure + drought; 2) Cover crops + drought; 3) Cattle manure + cover crops + drought; 4) Fallow and without cattle manure + drought; 5) Cattle manure without drought; 6) Cover crops without drought; 7) Cattle manure + cover crops without drought; and 8) Fallow and without drought. The treatments will be repeated six times. Composted cattle manure will be applied superficially at a rate of 20 Mg per hectare immediately after cotton harvest (season 2024). Cover crops will be the intercropping of winter wheat and field pea. Leaf area index (LAI) will be measured and plant sampling at 30, 60, 90 and 120 days after emergence (DAE); canopy and soil temperature will be measured (pinhead square until first open boll). At the same time, soil moisture readings will be taken. The harvest will be carried out manually and the productivity, number of bolls and the average weight of bolls will be determined. After harvesting, a soil sampling will be made (0.0-0.20 - 0.20-0.40 m depth) to determine the total organic carbon and its chemical (fulvic and humic acid) and physical fractions. The data will be submitted to analysis of variance and regression and for significant effects the means compared by Tukey's test (p <0.05).