Greenhouse whitefly

tomato, roses, gerbera and poinsettia. Damage symptoms The larvae of whitefly need a lot of protein for growth, and thus consume a large quantity of plant [...] larva stadium develops into a white, oval case encircled by a ring of erect waxy rods. This is called the pupa stadium and these pupae are found on the [...] plant sap. This contains a high proportion of sugar, and the excess is excreted as honeydew, with larger larvae expelling large quantities. The damage that

Phytophthora blight

Oomycetes and are therefore strictly speaking not fungi. They thrive at soil temperatures between 15 and 23 °C and higher water content than is optimal for [...] germination and attract the zoospores. The pathogen grows into the stem and on the plant surface and new sporangiophores (structures containing sporangia, a type [...] ting and be careful with overhead irrigation since both a high water content of the soil and water splash promote disease. Ensure fast drying and wound

Damping-off

roots rot and very little of the root system survives. On the border between air and soil or substrate the plant turns brown. A typical symptom of a Pythium [...] the Oomycetes, a separate group of microorganisms and is therefore not a real fungus. It survives as oospores, resting spores which are resistant to unfavourable [...] General Pythium is considered a ‘weak pathogen’, meaning that it can usually only affect plants that are in a sub-optimal condition or suffer from stress

Fusarium wilt

General Fusarium is a group of soil-borne fungi with many different species. Fusarium is widespread and can infect a range of host crops. Many species [...] blight in cereals and post-harvest decay. Fusarium oxysporum is the species causing vascular wilt. First the leaves turn yellow and wilt, mostly on one [...] pathogenic on a limited number of crops. Even within one crop, different formae speciales may occur and cause different symptoms. Fusarium oxysporum is the only

Obscure mealybug

growth and causing deformation and / or yellowing of leaves, sometimes followed by defoliation. The overall effect is a reduction of photosynthesis and therefore [...] world with a temperate climate. It has a very similar appearance to the citrus mealybug (Planococcus citri) , but its body is covered with a thicker layer [...] the males form a dark false pupa followed by a pupa in rapid succession. The actual pupa develops inside a white, cottony cocoon. After a complete metamorphosis

Tobacco whitefly

whitefly need a lot of protein for growth, and thus consume a large quantity of plant sap. This contains a high proportion of sugar, and the excess is excreted [...] tabaci ) is feared because of its high level of resistance to many insecticides and its propensity for the transmission of viruses. Life cycle and appearance [...] egg, first, second, third and fourth larval stage (often referred to as ‘pupa’ although strictly spoken this is not true) and adult. The larvae are found

Beet armyworm

during the day and is active only at night. The forewings are grey-brown suffused with a dark brown or black. The head and thorax are brown and the abdomen [...] The colour and pattern of the caterpillars is highly variable and depends partly on the host plant, the stage of development and the climate. A full-grown [...] plants such as chrysanthemum, gerbera, roses and potted plants. In both the greenhouse and the field, it is a major pest of sweet pepper. Damage symptoms

Anagyrus vladimiri

dimorphism: the female is about 1.5-2 mm in length and brown, with distinctive black and white banded antennae. The male is 0.8 mm in length and black in colour [...] Anagyrus vladimiri is a parasitic wasp belonging to the Encyrtidae family. This parasitic wasp is particularly effective for mealybug control, a common pest affecting [...] the mummy. Anagyrus vladimiri has a strong photokinetic response, i.e. the female is strongly attracted to light and is inactive in darkness.

Whitefly

larvae need a lot of nutrients for growth, and thus consume a large quantity of plant sap. This contains a high proportion of sugar, and the excess is excreted [...] can wilt and drop. Such leaf damage can in turn influence the development of fruit and lead to a reduction in yield. By sucking plant sap and secreting [...] es: If the population is very large, feeding on plant sap can affect the physiology of the plant, as a result of which growth is retarded. In full sunlight

Cottony soft rot

as cottony soft root, is a plant pathogenic fungus. It has a very wide range of host plants. Damage symptoms The first symptoms of a cottony soft root ( [...] wilting and death of plants. Life cycle and appearance of Cottony soft rot Cottony soft root ( Sclerotinia sclerotiorum ) overwinters as sclerotia and mycelium [...] in dead and living plant material in or on the ground. Sclerotia germinate at temperatures between 4 and 26 °C with an optimum between 13 and 15 °C. G