Crazy roots, hairy roots, crown gall

yet been defined. The assumption is that the bacteria survive in the soil, but it is possible that first infection is from the propagation material. Infection [...] Furthermore, infection is characterized by excessive root growth (crazy roots). In greenhouse vegetables, the roots overgrow the substrate and in severe epidemics [...] caused by a change in the hormonal system of the plant resulting from the Rhizobium infection. Rhizobium rhizogenes puts a Ri-plasmid in the plant tissue

Grey mould

Botryotinia fuckeliana / Botrytis cinerea ) is a commonly found fungus in many environments. It survives in plant parts like bulbs and crop residues or [...] much vegetative growth, in order to maintain a microclimate which is not humid enough for grey mould Provide sufficient ventilation in greenhouse crops Remove [...] plants or plant parts in a closed plastic bag In tomato: prune with a knife and not by hand, to avoid rugged, irregular wound surfaces In cucumber: remove dead

Downy mildew of Cucurbits

germination free water is required. For most downy mildews, the optimum temperature is around 15 o C and the closer the temperature is to this, the shorter [...] underside of the leave fluffy growth appears which is first white and later turns grey-brown. This is actually the sporulation of the pathogens extruding [...] or surviving mycelium sporangia are formed, structures in which zoospores are produced. However, in downy mildews, sporangia often germinate directly and

Just How Compostable are Ulti-Mite Sachets?

Black leg of seedlings

Pythium affects roots, in particular those of seedlings. Infected plants lag in growth. Seedlings fall over (‘damping-off’). In slightly older plants, [...] 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 [...] turn yellow, for example in flower bulbs. At first, the plants recover during the night, but later the plants wilt irreversibly. In potted plants the flower

Gummy stem blight

cucumis (Didymella bryoniae) is a fungal plant pathogen that causes gummy stem blight. Damage symptoms Mycosphaerella cucumis in cucumber causes brown lesions [...] On the leaves, round and extending lesions may occur. In cucumber, the most important symptom is internal fruit rot, which can only be recognized from [...] cucumis survives in crop debris and produces the sexual ascospores and asexual conida simultaneously. The spores germinate when free water is present on the

Sportnem-T

of crane fly larvae, Noctuids, mole crickets and caterpillars in lawns. It is effective in a wide temperature range. Pests Larvae of crane flies (Tipulidae) [...] size 2,500 million – 10 sachets of 250 million in a box. Developmental stage Infective third-stage larvae (L3). Concentration 86% Steinernema carpocapsae [...] Spray the solution as soon as it is prepared and within a short timeframe. Do not store mixed suspensions Dosage Sportnem-T is typically applied at a rate of

Vine mealybug

effect is a reduction of photosynthesis and therefore the yield. Flowers and fruit often drop off. Plant sap is rich in sugars, but low in proteins. In order [...] present only in the male. After a complete metamorphosis, a winged male emerges from the pupa. The male is smaller (1 mm), dark orange in color with long [...] has no mouthparts. The female is larger (3 mm) and voluminous, has an elongated oval shape and has no wings. The body is covered with a fine waxy material

Cannabis aphid

the point that microscopic analysis of the head is required to distinguish them. The hop aphid is common in North American hops production; there have been [...] overwinter and produce the next generation of aphids in the spring. In greenhouses, sexual reproduction is very rare and only triggered if lighting signals [...] Although it was first described in 1860, the cannabis aphid ( Phorodon cannabis ; a.k.a. bhang aphid or hemp aphid) is a very new pest to North America

Potato aphid

the dorsal surface. In green individuals, this stripe is dark green, while in pink specimens it is dark red. This longitudinal stripe is specifically cha [...] aphid ( Macrosiphum euphorbiae ) is of North American origin, but is these days distributed throughout the world. It is a highly polyphagous species with [...] As a result, the plant’s growth is retarded giving rise to deformed leaves or, if the infestation occurs early enough in the season, the death of young