Chocolate lowland climate in the narrow band of latitudes where cacao is grown (20 degrees north and south of the equator), the commercial company Mars, Incorporated and the University of California, Berkeley are conducting genomic research in 2017–18 to improve the survivability of cacao plants in hot climates. Chocolate is made from cocoa beans, the dried and fermented seeds of the cacao tree ("Theobroma cacao"), a small, 4–8 m tall (15–26 ft tall) evergreen tree native to the deep tropical region of the Americas. Recent genetic studies suggest the most common genotype of the plant originated in the Amazon basin and
Witch's broom Witch's broom Witch's broom or witches' broom is a deformity in a woody plant, typically a tree, where the natural structure of the plant is changed. A dense mass of shoots grows from a single point, with the resulting structure resembling a broom or a bird's nest. It is sometimes caused by pathogens. Witch-broom disease caused by phytoplasmas is economically important in a number of crop plants, including the cocoa tree "Theobroma cacao", jujube ("Ziziphus jujuba") and the timber tree "Melia azedarach". Witch's broom can be caused by cytokinin, a phytohormone, interfering with an auxin-regulated bud. In normal plant function,