In relation to potential loss of OP's, carbamates, and B2 carcinogens, the following pests and products have been identified as important for citrus production in Texas. Key problems include mites, scales, leaf cutting ants and fire ants. Citrus rust mite and spider mites are common. Armored scale and soft scale insects are difficult to control. Present varieties are not resistant to insects.
Efforts are underway to develop transgenic cultivars with insect resistance.
Introduced beneficial insects control citrus blackfly and Florida red scale in managed groves. Diseases Diseases include fungal leaf spots such as greasy spot and melanose, which cause defoliation and fruit blemishes. Copper-based products are available for fungal leaf spots. Soil-borne diseases include Phytophthora foot rot. Essentially all commercial oranges and grapefruit varieties are grafted onto sour orange rootstock which tolerates Phytophthora foot rot.