Sustainable control of the HLB vector in citrus family farming

Scaling up integrated pest management focusing on the HLB vector in family citrus growing in Argentina, Uruguay, Paraguay and Bolivia

Context of the story

HLB (Huanglongbing) is the most destructive disease of citrus in the world, caused by a bacterium (Candidatus Liberibacter spp). It is transmitted by an insect vector (Diaphorina citri) or through already infected plants. So far there is no cure. Prevention is based on the use of healthy material, constant crop and vector monitoring, its control, and early elimination of infected plants.
At the moment, vector and crop control is scarce and, when carried out, phytosanitary applications on a fixed calendar basis prevail, mostly using products with higher levels toxicity lacking previous monitoring actions.
The vector insect is present in all four countries of the project platform, with the disease first detected in 2012 in Argentina, 2013 in Paraguay and in December 2022 in Uruguay.

Scale up integrated pest management with focus on the HLB vector in family citrus farming

The implemented initiative

In order to prevent the advance of HLB in the region, since 2019, it was proposed to adapt and disseminate integrated pest management (IPM) technology in the control of the HLB vector in family agriculture (FA). IPM demonstration plots were implemented, training, communication and social awareness actions were carried out. The impacts of IPM on sustainability, quality and economic analysis were evaluated. The platform was formed by: INTA/Fundación ArgenINTA (Argentina), INIA (Uruguay), FaCAF UNI/FundUNI (Paraguay), Autonomous Municipal Government of Bermejo (Bolivia), SENASA and FEDERCITRUS of Argentina and UPEFRUY of Uruguay. Team: 103 researchers, extensionists and communicators.

HLB citrus vector control in integrated pest management (IPM) context

The technological solution

IPM is based on systematic monitoring of the HLB vector (Diaphorina citri), natural enemies (Tamarixia radiata, etc.), plants with HLB symptoms, phenological monitoring and monitoring of other relevant diseases and pests. A network of IPM demonstrator plots (LD) and conventional plots (LC) was implemented, also monitored, but with regular management by the grower.
Based on the monitoring, control actions -biological, cultural, ethological and low-impact chemical- were implemented in the LDs. An alert system was activated for producers via cell phone and e-mail with free access to the BioTic INTA-FONTAGRO HLB Web portal, with the development of a prototype of a mobile App for uploading monitoring data.
The impact of IPM was evaluated in terms of sustainability, fruit quality at harvest and economic analysis.
A virtual and face-to-face training course for pest monitors with certification was technologically and pedagogically designed and a comprehensive communication strategy was implemented. Scaling was applied with a collective innovation management approach.

"I'm thinking of planting a lot of 300 new trees next to the demonstration lot, where we intend to apply the set of technologies offered by the project, funding it myself and start implementing this kind of management from the very beginning"

Interviews were conducted with 15 demonstrating producers to ascertain their level of knowledge regarding the HLB vector, integrated pest management (IPM), and the potential for scaling up.

Participating countries

Type of project

Agronomic Practices

Results

The results of the monitoring in the LD (IPM) versus LC show decreases of the HLB vector between 60-99% in 3 sites and an increase of natural enemies from 17% to 332% in 11 sites. The average environmental impact index in the evaluated LD was positive. The improvement in fruit quality was registered by lower incidence of diseases and/or less pest pressure. The economic analysis shows that direct IPM costs increased, with higher gross margins in some LD from the second or third season onwards. The following were designed and implemented: 3 editions of a virtual/on-site course for pest monitors on the INTA PROCADIS Web platform; an alert system with access to the BioTic INTA-FONTAGRO HLB Web platform; a prototype of a monitoring upload App; a graphic and digital communication campaign for the prevention and management of HLB-vector. Participatory workshops, training, 2 manuals published. More than 22,900 people reached.

Relevant data

Total monitoring carried out at 17 sites (LD and LC) systematized in a database

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Population decline of the HLB vector insect at Bella Vista, Corrientes, Argentina

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More natural enemies of the HLB vector in the LD at 11 sites (from 17% to 332%).

Producers who receive alerts by cell phone with access to the BioTic INTA - FONTAGRO HLB Web portal.

Certificates awarded in 3 editions of the virtual/on-site course for monitors from INTA PROCADIS + 1 Course manual published

Reached by project activities (workshops, lectures, courses, alert sistem, meetings) in 4 countries. More than 1900 women

Printed guides “HLB and its vector. Images and notes for field reconnaissance” delivered - Also in digital version - In addition 6 presentations of results at congresses