Curly top is a disease, first noted in the United States in 1898, which strikes various types of plants, including tomato

Tomato

The word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...

, chili pepper

Chili pepper

Chili pepper is the fruit of plants from the genus Capsicum, members of the nightshade family, Solanaceae. The term in British English and in Australia, New Zealand, India, Malaysia and other Asian countries is just chilli without pepper.Chili peppers originated in the Americas...

, eggplant, potato

Potato

The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family . The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species...

es, and others, causing them to stop growing or producing fruit, often eventually dying. Typically, the leaves curl up, giving it the name.

This disease may not immediately kill the plant, but will interrupt its life-cycle, causing poor or no flowering or fruiting.

It is carried almost exclusively by the beet leafhopper

Beet leafhopper

The beet leafhopper is a species of leafhopper with a longer, thinner build than most. It is found across much of the United States and Mexico, in South Africa and from the countries around the Mediterranean Sea to Central Asia ....

 or the hoverfly

Hoverfly

Hoverflies, sometimes called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while the larvae eat a wide range of foods...

, which can be managed through chemical means, or by use of companion plants; it is repelled by marigold

Tagetes

Tagetes is a genus of 56 species of annual and perennial mostly herbaceous plants in the sunflower family . The genus is native to North and South America, but some species have become naturalized around the world. One species, T...

s, while Pelargonium

Pelargonium

Pelargonium is a genus of flowering plants which includes about 200 species of perennials, succulents, and shrubs, commonly known as scented geraniums or storksbills. Confusingly, Geranium is the correct botanical name of a separate genus of related plants often called Cranesbills. Both Geranium...

geraniums and petunia

Petunia

Petunia is a widely cultivated genus of flowering plants of South American origin, closely related with tobacco, cape gooseberries, tomatoes, deadly nightshades, potatoes and chili peppers; in the family Solanaceae. The popular flower derived its name from French, which took the word petun, meaning...

s function almost identically as trap crop

Trap crop

A trap crop is a plant that attracts agricultural pests, usually insects, away from nearby crops. This form of companion planting can save the main crop from decimation by pests without the potential issues and controversy involved in using pesticides....

s.