Priming of seeds of Urochloa humidicola cv Llanero with signaling molecules

• Grant number: 24/07362-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2024
• Effective date (End): July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Ceci Castilho Custódio
• Grantee: Giulia Muniz Peres
• Host Institution: Pró-Reitoria de Pesquisa e Pós-Graduação. Universidade do Oeste Paulista (UNOESTE). Presidente Prudente , SP, Brazil

Abstract

Brazilian livestock farming is based on the large area of existing pastures, both natural and cultivated, with the vast majority of areas being cultivated with grasses of the Urochloa genus, especially the species U. brizantha, U. ruziziensis and U. humidicola. However, as they are non-domesticated plants, these materials present seeds with de-graining and dormancy. One way to break dormancy is scarification with concentrated sulfuric acid, which breaks the protective integuments and allows greater gas exchange, but generates a highly polluting residue. Some molecules, such as sodium nitroprusside, hydrogen peroxide and ethanol, have characteristics that help to break dormancy and increase the speed of germination and colonization of the soil, which makes it difficult for invasive plants to settle. Thermal treatments can also stimulate the breaking of dormancy, by simulating the increase in temperature due to fire in natural environments. The objective of this work will be to verify the effect of pre-treatment, via priming or physiological conditioning, with sodium nitroprusside, hydrogen peroxide and ethanol on two batches of Urochloa humidicola cv. Llanero, one scarified and the other not scarified, combined or not with treatment with heated air on the germination and initial development of seedlings. The evaluations will be germination and viability, germination speed and determination of hydrogen peroxide content, in addition to water content before and after physiological conditioning treatments. The design will be completely randomized with 12 treatments and four replications for each seed lot and test product.