• Circular scale

  January 1, 1970

  citrus industry. In more northern countries of its range, it occurs in greenhouses. In addition to citrus, it occurs on many other plants. Damage symptoms [...] In citrus, it tends to prefer the lower and central parts of mature trees. Circular scale prefers the leaves, but in high infestations it may spread to [...] Chrysomphalus aonidum is a tropical species, native to the Oriental region but it has been dispersed widely in tropical and subtropical parts of the world,

• Pepper weevil

  January 1, 1970

  forms a cavity and covers it with its excrement, creating a type of cell, to be used later when it begins its metamorphosis. It develops a shiny white colour [...] yellow before wilting and dropping off. When you see fruit on the ground, it is clear that the crop has been very severely damaged. Lifecycle and appearance [...] hatching. In total, the larva passes through three larval stages during which its only activity is feeding; the larval stage lasts around seven to eight days

• Powdery mildew

  January 1, 1970

  hardens the cell walls and makes it harder for the fungi to enter the leaves To reduce chances of powdery mildew in greenhouses, it is advised to first ventilate [...] to powdery mildew infection by dropping leaves that are not infected yet. It depends on the cultivar how soon after infection this happens. In apple, pear

• Zucchini

  January 1, 1970

  light green) belonging to the cucumber family. It is also referred to as marrow or summer squash and it is eaten as a vegetable. Together with a number [...] number of other varieties of squash and pumpkin, it belongs to the species of Cucurbita pepo . This species grows in tropical regions of all continents, especially

• Aphidius ervi

  January 1, 1970

  been widely utilized in various agricultural regions around the world due to its effectiveness. An Aphidius ervi female wasp can parasitize hundreds of aphids [...] slabs or in Diboxes Make sure the material remains dry and is not moved from its introduction site for at least a few days The dosage of Ervipar depends on [...] Aphidius ervi Aphidius ervi exhibits a specialized feeding behavior that makes it an effective biological control agent against aphid pests. Once the female

• Angular leaf spot

  January 1, 1970

  forms on the underside of the leaf. This exudate changes to a white film when it dries. Lesions may merge as they grow and later also become visible on the [...] humidity or presence of water. These conditions occur mostly in the spring if it rains or when sprinkler irrigation is used. Healthy, well growing plants are

• Pierce's disease of grapevine

  January 1, 1970

  fastidiosa is a gram-negative bacterium which is limited to xylem tissue. It has many hosts, many of which show minor or no symptoms. More and more plant [...] is best known in grapevine, stone fruit (peach and plum) and citrus, where it causes diseases such as Pierce's disease of grapevines, phony peach disease [...] leaf scald, citrus variegated chlorosis and quick decline syndrome. Recently, it is becoming more problematic in olive. Damage symptoms Grapevines: Primary

• Roots Growers positive about Mycotal against whitefly

  January 1, 1970

  parasitic wasps and predatory bug. ‘It goes without saying that Mycotal’s biological nature is a big plus, as it means we can use it almost indefinitely and the [...] improved effectiveness means that it not only combats whiteflies even better than before, but RD studies proofs that it can also efficiently controls a range [...] crucial factor. ‘We obviously want our cultivation to be as organic as possible. It has to be, as there’s only one chemical product against whitefly in tomato

• American serpentine leaf miner

  January 1, 1970

  American serpentine leaf miner (Liriomyza trifolii) eats its way outwards from its egg, so that its mines join to form small plates. In various other crops [...] gerbera, gypsophila, celery, sweet pepper, pea, bean and potato. In greenhouses, it is mainly found on gerbera and chrysanthemum. Today the insect is widespread [...] forms of tunnelling between these ‘plate mines’ and normal mines, making it an unreliable criterion for the identification of the species. Indirect damage

• Foot rot of cereals

  January 1, 1970

  health and yield. Microdochium nivale thrives in cool, moist conditions, making it particularly problematic in temperate regions. Damage symptoms M. nivale is [...] can also occur. Foot rot becomes obvious from late stem extension onwards. It results in dark-brown staining of the lower nodes. Long dark streaks may also