Aphids
Aphids pose a significant threat to tomato crops, with various species causing notable damage. The most common species on tomato are the Glasshouse potato aphid or Foxglove aphid (Aulacorthum solani) and the Potato aphid (Macrosiphum euphorbiae). To a lesser extent also the Peach potato aphid (Myzus persicae) and the Cotton aphid (Aphis gossypii) can be found in tomato. The Glasshouse potato aphid (Aulacorthum solani) has a particular affinity for tomato plants and can stunt their growth by extracting sap from the leaves and stems. Additionally, the Potato aphid (Macrosiphum euphorbiae) can cause distorted growth and leaf curling, aphids can transmit various viruses such as Potyvirus (potato virus Y) which can devastate tomato crops.
Leaf miners
Leaf miners are a challenge to tomato crops, and several species stand out as significant pests. Tomato leaf miner (Liriomyza bryoniae), Pea leaf miner (Liriomyza huidobrensis), and American serpentine leaf miner (Liriomyza trifolii) are among the most notorious leaf miner species affecting tomatoes. These tiny insects lay their eggs in tomato leaves, and the larvae that hatch proceed to tunnel through the leaf tissue, creating distinctive winding mines that can severely damage the foliage. As a result, the plant's ability to photosynthesize and produce energy is compromised, leading to reduced yields and overall weakened tomato plants.
Mealybugs
In some cases, mealybugs, and in particular the obscure mealybug (Pseudococcus viburni) can be a problem in tomato. These small, soft-bodied insects can be found mostly on the stems where they feed on the sap of tomato plants, causing stunted growth and yellowing of the leaves. Their waxy, cotton-like appearance makes them easily recognizable on the plant surfaces. Mealybug infestations can weaken tomato plants, reducing their ability to produce healthy fruits and impacting overall yields.
Caterpillars
Caterpillars pose a significant threat to tomato crops, with several notorious species causing substantial damage. The tomato leaf miner moth (Tuta absoluta) is an increasing problem worldwide, it is devouring tomato foliage and inflicting significant harm to the entire plant. The Tomato looper (Chrysodeixis chalcites) feeds voraciously on tomato leaves, leading to defoliation and reduced plant vigour. The Tomato moth (Lacanobia oleracea) can cause both leaf and fruit damage, further exacerbating the yield loss. The Cotton bollworm (Helicoverpa armigera) and the Beet armyworm (Spodoptera exigua) also target tomatoes and can cause extensive fruit damage, leading to economic losses for growers. Tomato pinworm (Keiferia lycopersicella) is another formidable pest, tunnelling into tomato fruits making them susceptible to secondary infections.
Spider mites
Two-spotted spider mites (Tetranychus urticae) pose a significant threat in tomato crops. This notorious mite feeds on tomato plants by piercing the plant cells and extracting sap, leading to stippling, yellowing, and ultimately, reduced photosynthesis. These mites are particularly problematic in hot and dry conditions, and their rapid reproduction can result in widespread infestations that weaken tomato plants and hinder fruit production.
Thrips
Thrips are notorious pests on tomato crops, especially Western flower thrips (Frankliniella occidentalis). These tiny insects feed on the tender parts of tomato plants, including leaves, stems, and fruits, causing stippling, discoloration, and distortion of the plant tissues. Thrips have piercing-sucking mouthparts that enable them to extract plant fluids, leading to reduced plant vigour and diminished fruit quality. On the fruit thrips feeding causes 'ghost rings’. Moreover, thrips can also transmit certain plant viruses, exacerbating the damage and posing further threats to tomato crops.
Whiteflies
Whiteflies can be highly problematic in tomato crops, with two notable species of concern being Tobacco whitefly (Bemisia tabaci) and Greenhouse whitefly (Trialeurodes vaporariorum). These small, winged insects feed on tomato plants by piercing the phloem and extracting sap, leading to yellowing, wilting, and reduced plant vigour. Whitefly infestations can cause significant damage, hinder fruit development, and ultimately impact tomato yields. Furthermore, whiteflies are known to secrete honeydew, promoting the growth of sooty mold that further interferes with photosynthesis.
Plant bugs
In certain cases, plant bugs can be a concern in tomato crops, in particular the species Nezara viridula, Nesidiocoris tenuis and Engytatus modestus. The green stink bug (Nezara viridula) can be a major pest, piercing tomato fruits and sucking out their juices, leading to fruit deformation and reduced quality The tomato bugs Nesidiocoris tenuis and Engytatus modestus are beneficial predators that feeds on various pests, including whiteflies, thrips and small caterpillars, making it a valuable ally in integrated pest management strategies. However, they can become a problem if their density becomes too high, as they may then feed on tomato fruits, causing damage.
Other pest mites
Tomato russet mite (Aculops lycopersici) can be a severe problem in tomato. These tiny mites feed on tomato leaves and stems. Affected areas turn a rusty brown colour, leaves becoming slightly curved with a silvery shine on the underside. Considerable damage can occur at high density when eventually fruits will also be affected, and leaves dry out quickly. Damage is first seen on the lower parts of the plants and moves upwards when mites ascend.