Citrus Huanglongbing (HLB), also known as citrus greening, continues to pose a significant threat to the global citrus industry, with nearly 50 countries across Asia, Africa, the Americas, and Europe affected. In Brazil, the incidence rate of HLB surged to 38.06% in 2023, up from 24.42% the previous year. The cost of plant protection has skyrocketed, especially due to a 42% increase in the sales of insecticides aimed at controlling the citrus psyllid vector, which now covers 98% of Brazil’s citrus planting areas. Similarly, Florida’s citrus industry has been devastated, with an 80% decline in production since the disease was first detected in 2005.

Urgent Pesticide Approvals and Global Race for Control Solutions

As the severity of HLB increases, many countries have urgently authorized the use of new and existing pesticides to control the disease. In Brazil, the Ministry of Agriculture (MAPA) has assessed Bayer’s new pesticide ingredient Spidoxamat (Plenexos) due to the urgency of addressing HLB. In Portugal, the insecticide Teppeki (flonicamid) was approved in 2021 for controlling the African citrus psyllid, while the United States re-approved the banned insecticide Aldicarb (Temik®) for use in controlling HLB in 2021. These emergency measures highlight the global race to find effective control solutions.

Agrochemical Companies Introduce Specialized Control Products
Leading agrochemical companies such as Syngenta, Adama, and Sipcam Nichino have also introduced specialized products aimed at controlling the citrus psyllid, the primary vector of HLB. Syngenta launched its broad-spectrum insecticide Minecto® Pro at Expocitros 2023, containing cyantraniliprole and abamectin. This product not only controls the psyllid but also helps manage pest resistance. Adama introduced Trivor, a combination of acetamiprid and pyriproxyfen, which targets all stages of the psyllid lifecycle, from eggs to adults. Sipcam Nichino launched Fiera (buprofezin) and Fujimite (fenpyroximate), both designed to tackle psyllid nymphs with growth-regulating effects and contact action.

Biopesticides and Eco-Friendly Alternatives to Chemical Solutions

Alongside chemical solutions, biopesticides are emerging as effective alternatives. Brazilian biotechnology company Vittia launched the bioinsecticide IZATURBO, which is formulated from the entomopathogenic fungus Isaria javanica. Similarly, Oxiquímica Agrociência introduced MIRA, a plant-derived insecticide that uses natural active ingredients to combat the citrus psyllid.

Advancements in Nanotechnology and Gel-Based Formulations

Innovative technologies such as nanotechnology and gel-based formulations are also playing a significant role in improving the efficiency of HLB control. In Brazil, Embrapa and the University of Campinas have developed a nano-insecticide that controls the release of thiamethoxam, reducing the required application dose by half. This new formulation shows higher application efficiency, reduced environmental impact, and slower pest resistance development. The Chinese Academy of Agricultural Sciences has also developed a cycloxaprid water-based gel, which enhances penetration and stability on citrus leaves, showing over 20% better performance than traditional wettable powders.

Plant Immunity Activation and New Genetic Approaches

Beyond these advancements, a new approach is emerging in the form of activating the plant’s innate immunity. Researchers at the U.S. Department of Agriculture’s Agricultural Research Service (ARS) have discovered a method to enhance citrus trees’ natural resistance to HLB by integrating pathogen-recognizing receptors into the plants’ DNA. This breakthrough could revolutionize HLB control, offering a more sustainable and natural defense against the disease. Similarly, Purdue University has developed a nano-carrier technology that delivers antibiotics directly to the citrus tree’s phloem and roots, targeting the bacteria that cause HLB.

Groundbreaking Solutions by Invaio Sciences and Silvec Biologics

Two companies, Invaio Sciences and Silvec Biologics, are also at the forefront of developing groundbreaking solutions. Invaio Sciences launched its Trecise™ technology, which delivers active ingredients directly into the vascular system of citrus trees, reducing chemical usage by up to 90%. This technology, which was trialed in Florida in 2023, has shown a 30% increase in citrus yields. Invaio has also partnered with the global agricultural trader Louis Dreyfus Company (LDC) to introduce this technology in Brazil, furthering its reach. Silvec Biologics, in collaboration with Southern Gardens Citrus and the University of Florida, has developed an RNA-based product that uses a reprogrammed virus to express antimicrobial peptides, offering a cost-effective and highly effective way to reduce HLB’s impact.

Hope for the Future of Citrus Farming

These innovations, along with the ongoing research and development efforts, are providing hope for the future of citrus farming. As the global citrus industry continues to face the threat of HLB, the combination of new chemical solutions, biopesticides, advanced technologies, and genetic breakthroughs offer promising avenues for managing and ultimately overcoming this devastating disease.

Source- Invaio