Cutworms

appearance of Cutworms The adults of Agrotis spp. have pale grey to grey-brown forewings with a faint kidney-shaped marking and a red spot. They have broad hindwings [...] night and hide in the ground during the day. Damage from these instars is usually observed as a cutting of young seedlings, often causing death of the cut [...] the stems of young plants. This is where their common name comes from. Cutworms are vey polyphagous and have a wide host range. Life cycle and appearance

Two-spotted spider mite

tomatoes and cucumbers, as little as 30% damage of the leaf surface can lead to loss of the crop. The nymphs and adults also produce webs, and plants can get [...] protonymph, deutonymph, and adult. In the larval and nymphal stages, an active period and a resting period of roughly equal duration can be distinguished. Eggs [...] nymphs and adults cause damage to the host plant by feeding on plant sap. They mainly occur on the underside of leaves where they pierce the cells and suck

Greenhouse whitefly

covered with a white waxy substance. Damage symptoms The larvae of whitefly need a lot of protein for growth, and thus consume a large quantity of plant sap [...] feeding on plant sap can affect the physiology of the plant, as a result of which growth is retarded. In full sunlight, leaves can wilt and fall. Such leaf [...] emerges from the pupa via a T-shaped fissure. The adult whiteflies can usually be found in the top of the plant and on the underside of young leaves, where they

Apple scab

research that has been done on the influence of climatic conditions on release of ascospores and risk of infection, a decision support systems has been build [...] ascomycete fungus that causes apple scab disease Life cycle and appearance of Apple scab Venturia inaequalis overwinters in the form of unripe fruiting bodies [...] the cuticula. The asexual conidia are released and repeat the cycle of infection of new plant parts and spore production. In autumn, the fungus produces

Oleander aphid

occur under conditions of overcrowding and when plants are senescing. The parthenogenetic mode of reproduction, high fecundity, and short generation time [...] shoots of the host plants. The damage caused by the aphid colonies is mainly aesthetic due to the large amounts of sticky honeydew produced and the resulting [...] also called the milkweed aphid, is a common pest of several important ornamental plants in the families Apocynaceae and Asclepiadaceae. It is commonly found

Onion thrips

prepupa, pupa, and finally the adult insect. The eggs of the onion thrips (Thrips tabaci) are laid in leaves, flower petals and in the soft parts of stalks. They [...] plant tissue with a saw-like ovipositor. Larvae are light to yellowish green in colour, with a large head and bright red eyes. The colour of the adult depends [...] Damage symptoms Thrips cause damage to plants by piercing the cells of the surface tissues and sucking out their contents, causing the surrounding tissue

Gummy stem blight

drops, tools and hands of workers. The ascospores are the main source of dispersal of disease upwards in the crop and the conidia for spread of the disease [...] bryoniae) is a fungal plant pathogen that causes gummy stem blight. Damage symptoms Mycosphaerella cucumis in cucumber causes brown lesions on the foot and higher [...] narrowing of the tip of the mature fruits. The symptoms on stems, leaves and inside the fruits may occur together or individually. Life cycle and appearance

Leaf stripe

the base of the leaf and the leaf sheath. They gradually extend and become brown and chlorotic and may merge. Eventually this leads to the death of the leaf [...] graminea is a disease of Barley that causes significant yield losses. Damage symptoms Symptoms first occur on the first, second and third leaf and subsequently [...] may be stunted and heads may be distorted and failing to emerge from the sheath. Ear length and the number of kernels may be reduced and kernels may be

Brown root rot, corky root rot

wilts caused by Verticillium or Fusarium . Progressive disease causes more and more destruction of the root system and subsequent loss of vigour and further [...] lycopersici is a fungal plant pathogen, infecting tomatoes and aubergine. It causes brown root rot and corky root rot. Damage symptoms The first signs of this disease [...] through dispersal of soil particles by farm equipment and cultivation practices. However, this fungus is a poor competitor against a balanced microbial

Spotted Wing Drosophila

2-3 mm in lengthg, and have a wingspan of 6-8 mm. Males are smaller than females. They can be easily distinguished from males of other Drosophila species [...] Europe where it has caused severe yield losses in many berry crops, cherries and grapes. Life cycle and appearance of Spotted wing drosophila Adult spotted-wing [...] bacteria, fungi and yeasts). Finally, deterioration of fruit can increase its susceptibility to attack by other Drosophila species. D. suzukii has a wide host