• Apple collar rot

  borders occur. Above the graft and on leaves, dark brown, irregular lesions occur. In strawberry, the heart leaves wilt first, then the whole plant. Life [...] host range. Damage symptoms Phytophthora cactorum causes seedling damping off, a reduced root system and black discolouration of the roots. On the foot, [...] germination and attract the zoospores. The pathogen grows into the stem and on the plant surface and new sporangiophores (structures containing sporangia

• Thrips

  All thrips species that cause damage in green-houses belong to the family Thripidae. Thrips damage Thrips cause damage to the plant by piercing the cells [...] With a serious infestation the leaves themselves can shrivel, and there can be varying levels of fruit damage depending on the species of thrips and their [...] population density. In ornamentals , flowers can be seriously damaged, while leaves are often damaged and become misshapen. Thrips are also responsible for the

• Phytophthora blight

  growth on the leaves. The centre is grey-brown with a light-green edge. On the stem, elongated brown lesions occur, usually circling the stem. On potato [...] early blight of potato. Damage symptoms Phytophthora causes root rot, seedling damping off and rot of stems, bulbs, tubers, leaves and fruits. Late blight [...] germination and attract the zoospores. The pathogen grows into the stem and on the plant surface and new sporangiophores (structures containing sporangia

• Leaf miners

  are damaging pests that tunnel through leaves, reducing photosynthesis and weakening plant growth. Their feeding patterns cause visible leaf damage, lower [...] that cause most damage all belong to the genus Liriomyza and are very common in temperate regions. Leaf miner damage Leaf miners cause damage to plants both [...] pests. The leaf miner species that cause damage in horticultural crops are mostly polyphagous; that is, they feed on many crops. However, this is not universal

• Blight of pepper

  important commercial crops. Damage symptoms Phytophthora causes root rot, seedling damping off and rot of stems, bulbs, tubers, leaves and fruits. Several P [...] The small roots die and brown-black lesions occur on the larger roots. Plants wilt and the crown leaves drop off. Life cycle and appearance of Blight of [...] germination and attract the zoospores. The pathogen grows into the stem and on the plant surface and new sporangiophores (structures containing sporangia

• Cercospora leaf spot

  coalesce. The spots dry up results in shot-hole appearance to the leaves. Severely infected leaves drop off prematurely results in reduced yield. Stem, petiole [...] leaf spots can be caused by many species of Cercospora species depending on the plant type infected. Infected seeds, infected plants and plant debris

• Bacterial wilt, brown rot

  potential host plants. Damage symptoms In potato, field symptoms of Ralstonia solanacearum are wilting and yellowing of leaves and stunted plants. Inside [...] through infected tubers, the wilting and collapse of plants happens rapidly. Leaves remain green after wilting, until they are completely desiccated. Infected [...] which is not seen in Clavibacter -infected plants. In tomato, the youngest leaves are affected first. They show signs of wilting during the day which may

• Codling moth

  first generation adults appear from mid May onwards. Eggs are laid singly on leaves or developing fruitlets and hatch after 10-14 days. The first instar larvae [...] Fully grown larvae leave the fruits and spin cocoons under loose bark, cracks in trunks or supporting stalks, or other places. Depending on the climate, there [...] y of pear, quince, peach and other fruits. It is very common in Europe. Damage symptoms After invading the fruit, the larvae first form a small cavity

• Leaf stripe

  significant yield losses. Damage symptoms Symptoms first occur on the first, second and third leaf and subsequently on other leaves. Yellow stripes are formed [...] fungus spreads from the seed into the seedling. Conidia are produced on the infected leaves when humidity is high and wind-dispersed to neighbouring ears where

• Asian citrus psyllid

  disease. Damage symptoms The psyllid is a sucking insect that inserts its mouthparts into plant tissue to feed. Adults feed on young stems and on leaves of all [...] feed on young leaves and stems, continuously secreting copious amounts of honeydew and a thread-like waxy substance so black sooty mold develops on the [...] honeydew. Their feeding damages citrus by burning back new shoots or causing leaves to twist or notch as they mature. Worst damage is done when the insect