Evaluation of the effect of citrus phytocystatins on the development of nymphs and adults of Diaphorina citri through feeding on an artificial diet.

• Grant number: 25/05076-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2025
• End date: June 30, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Sâmara Vieira Rocha
• Grantee: Gabriela Trevisan Waideman
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Brazil is currently the largest producer and exporter of oranges in the world. However, citrus groves have been suffering severe damage caused by pests and diseases for which there are few effective control measures. Huanglongbing (HLB), known as greening, is the most serious disease of citrus. The disease is associated with the bacterium Candidatus Liberibacter spp. and mainly affects the phloem vessels, compromising the growth and development of the fruit, resulting in low juice content and high acidity, making it commercially unviable and resulting in serious economic losses. The main vector transmitting the bacteria to citrus plants is the insect Diaphorina citri (Hemiptera: Liviidae). Due to the impossibility of cultivating the bacteria associated with HLB, measures to combat the disease have been directed at controlling the insect vector. Since D. citri uses cysteine ¿¿peptidases in its digestive processes, an alternative for controlling this insect consists of using cysteine ¿¿peptidases inhibitor proteins, called cystatins, which are naturally present in plants. Thus, this proposal aims to carry out feeding trials with the insect D. citri on an artificial diet containing citrus cystatins, aiming at interfering in the insect's development and as a possible control measure. (AU)