| Apple chat fruit MLO | |
| Common Names: | apple small fruit, chat fruit of apple |
| Causal Agents: | Phytoplasma |
| Hosts: | apple trees |
| Distribution: | Europe, parts of North America, South Africa, New Zealand |
| Symptoms: | delayed fruit development, smaller green apples during harvest, delayed fruit drop, circular spots on the apples |
| Treatment: | precautions during grafting |
Apple chat fruit MLO, also known as "apple small fruit" and "chat fruit of apple",[1] is a mycoplasma-like organism (MLO)[2] that affects only apple trees, specifically Lord Lambourne and Tydeman's Early Worcester,[3] though in North America, Turley, Winesap, Jonathan, and Golden Delicious can be affected.[4] Symptoms include delayed fruit development, smaller green apples during harvest, delayed fruit drop, and circular spots on the apples themselves.[3] [5] The disease is widespread throughout Europe, especially England and Wales, but is also present in parts of North America, South Africa, and New Zealand.[3] There are no known insect vectors and no transmission method other than grafting is known.[4] The disease itself is not fully systemic[3] and virulency is varied among individuals.[4]