text: Bacterial wilt is another common disease impacting yield. Wang et al., 2019 found phage combination therapies to reduce the impact of bacterial wilt, sometimes by reducing bacterial abundance and sometimes by selecting for resistant but slow growing genetics.
  Pests
  Some common tomato pests are the tomato bug, stink bugs, cutworms, tomato hornworms and tobacco hornworms, aphids, cabbage loopers, whiteflies, tomato fruitworms, flea beetles, red spider mite, slugs, and Colorado potato beetles. The tomato russet mite, Aculops lycopersici, feeds on foliage and young fruit of tomato plants, causing shrivelling and necrosis of leaves, flowers, and fruit, possibly killing the plant.
  After an insect attack tomato plants produce systemin, a plant peptide hormone. Systemin activates defensive mechanisms, such as the production of protease inhibitors to slow the growth of insects. The hormone was first identified in tomatoes, but similar proteins have been identified in other species since.
  Other disorders
  Although not a disease as such, irregular supplies of water can cause growing or ripening fruit to split. Besides cosmetic damage, the splits may allow decay to start, although growing fruits have some ability to heal after a split. In addition, a deformity called cat-facing can be caused by pests, temperature stress, or poor soil conditions. Affected fruit usually remains edible, but its appearance may be unsightly.