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
Cacao swollen-shoot virus the whole plantation. Since the virus is transmitted readily through seed, only seed that is known to be free of the virus should be planted. "Planococcus njalensis" population density is closely correlated with density of ants in the genus "Crematogaster", which build protective carton tents over the mealy bug colonies. "Crematogaster" populations however are negatively correlated with populations of ants of the genus "Oecophylla". This could be a natural biological control that is worth considering if agents to control the "Crematogaster" ants are developed, since they should not target "Oecophylla" ants as well. Cacao swollen shoot virus has had a