A research team in China has filed a patent application for a new approach to citrus greening prevention. It is based on activating the plant’s own immune system through herbal extracts and microbial treatments. The announcement, reported by Fruitnet on 31 October 2025, illustrates how the search for alternatives to broad-spectrum chemistry is expanding worldwide.

An immunity-based approach

The Newkis Citrus HLB Prevention Research Team, based in Guangzhou, China, announced late last year that it has filed an invention patent application in Australia for a new method to prevent and control Huanglongbing (HLB), or citrus greening. The team has been developing and field-testing the approach across Chinese citrus-growing provinces (Jiangxi, Guangdong, Guangxi and Hunan) since 2015.

According to Newkis, the method combines herbal extracts, functional microorganisms and what the company describes as “low-frequency energy water” into a single treatment programme. The aim is to activate the plant’s innate immune signalling pathways in order to  enhance the plant’s resistance to HLB. In a press release quoted by Fruitnet, the team further claims that continued application can help citrus trees establish long-term immune memory within the rhizosphere ecosystem.

The patent was developed by Zhu Weiping, an agronomist and microbiologist based in Guangzhou, together with the Newkis Ecological Energy Research Team. The company has said that ongoing validation work is under way.

The wider plant-immunity effort

The search for plant-immunity-based approaches to HLB is one of the most active areas in citrus research today. CITRUSBUSTERS is pursuing it on several fronts, too. In Work Package (WP) 2, Universidad Politécnica de Madrid (UPM) is extracting immune-priming biofractions from citrus peel waste. A recent open-access review by the same team in The Plant Journal explains, in detail, how plants recognise and respond to pathogen signals. In WP 1 and WP 3, Bioclear Earth is investigating both the detection potential and the biocontrol potential of the citrus microbiome. In WP 1, the Centro de Citricultura Sylvio Moreira – Instituto Agronômico (CCSM-IAC) is evaluating large mutagenised citrus populations under natural disease pressure to identify promising genotypes with potential disease tolerance.

It is worth noting that plants do not produce antibodies in the immunological sense of the word. They rely on innate immunity, which can be primed by molecular signals but does not include the antibody-based adaptive immunity of vertebrate animals. Comparisons with antibodies are therefore metaphorical, and long-term protection from citrus greening will almost certainly require multiple, complementary tools rather than any single treatment.

Still, the direction of travel matters. Approaches that work with plant biology, rather than relying only on conventional chemical treatments, are closely aligned with the direction being explored within CITRUSBUSTERS – towards greener and more sustainable solutions for the future of the global citrus industry.

 

This article is based on: Caggiati, B. (2025). New breakthrough in management of HLB. Fruitnet, 31 October 2025.

Source: https://www.fruitnet.com/produce-plus/new-breakthrough-in-management-of-hlb/269496.article