Jujube witches' broom virus

Jujube witches' broom virus (Mersevirus jujubae) is a severe phytoplasmal disease affecting the jujube tree (Ziziphus jujuba). The pathogen invades the phloem tissue, disrupting nutrient transport and causing significant hormonal imbalances within the host plant.

The disease specifically impacts jujube plantations, posing a major threat to commercial fruit production. It is a systemic infection, meaning that once the phytoplasma establishes itself, it spreads throughout the entire vascular system, eventually leading to the decline and death of the host.

The hallmark symptom is the formation of dense, cluster-like shoots, commonly referred to as "witches' brooms," arising from adventitious buds. Other visible signs include:

• leaf chlorosis and reduced leaf size;
• stunted growth of branches;
• failure of flower and fruit set;
• necrosis and dieback of affected tree parts.

The spread of this pathogen is primarily driven by insect vectors, particularly leafhoppers, which acquire the phytoplasma while feeding on infected trees and transmit it to healthy ones. Environmental conditions that favor the proliferation of these insect vectors significantly increase the incidence of the disease in orchards.

Management strategies focus on prevention and sanitation, as there is no chemical cure for phytoplasmas. Growers must prioritize the use of certified, disease-free nursery stock, implement strict insect control programs to manage vector populations, and immediately remove and destroy any infected trees to prevent further spread.