Noah's planthopper

Noah's planthopper (Reptalus noahi) is a significant insect species belonging to the order Hemiptera and the family Cixiidae. In viticulture, it is recognized as a primary vector of dangerous phytoplasmas, most notably the pathogen responsible for the grapevine disease known as Flavescence dorée, which poses a severe threat to commercial vineyards worldwide.

The primary host for Reptalus noahi is the cultivated grapevine (Vitis vinifera). The insect feeds on the phloem sap of the plant, causing direct nutritional depletion. However, the most critical damage is caused by the transmission of phytoplasmas into the vascular system during the feeding process, which leads to systemic infection and chronic decline of the vines.

The biological cycle of this pest is strongly linked to the soil and the grapevine root system. The nymphs develop underground, feeding on the roots of the vine for an extended period. Once they reach the adult stage, they emerge above ground to feed on leaves and shoots, mate, and deposit eggs, completing the cycle that facilitates the transmission of diseases across the vineyard.

Damage symptoms are often characterized by yellowing and rolling of leaves, stunted shoot growth, and the wilting of inflorescences or clusters. Because the insect introduces pathogens, the vine may exhibit a weakened immune system, leading to poor winter hardiness and, ultimately, the death of the stock if the infestation is not managed properly in time.

Effective management requires an integrated pest management (IPM) approach to minimize the risk of phytoplasma spread. Recommended strategies include:

• Regular monitoring using yellow sticky traps to detect adult emergence;
• Strict control of weeds within and around the vineyard to remove alternative hosts;
• Timely application of systemic insecticides targeting the adult stage during the flight period;
• Planting only certified virus-free nursery stock to prevent the introduction of pathogens.