• Phytophthora blight

  between 15 and 23 °C and higher water content than is optimal for crop growth. Phytophthora overwinters in roots, infected tubers and bulbs or in the soil in [...] is by wind and rain causes the pathogen to be returned to the soil from infected plants. Dispersal in the soil happens via water, since the zoospores can [...] Life cycle and appearance of Phytophthora blight Phytophthora species are very destructive organisms belonging to the Oomycetes and are therefore strictly

• Click beetles

  cycle and appearance of Click beetles Adult Agriotis sp. are 6-10 mm long and yellowish brown to black. The eggs are laid in May or June in groups in the [...] fully grown the larvae pupate in the soil in summer. The adults appear about 4 weeks after pupation, but usually remain in the soil until the following spring [...] symptoms The click beetles feed on the roots and bore into the base of plants. This can cause the plants to wilt and die. Damage is more severe in young plants

• Oleander aphid

  nymphs rather than eggs and that the progeny are clones of the adult female. The nymphs feed in colonies on the shoots at the top of the plant. Nymphs progress [...] thus the adult aphids are all female and males do not exist. Adult females may be winged or wingless. The winged adult females (alata) are yellow and black [...] found in tropical to warm temperate regions throughout the world. It probably originated in the Mediterranean region, the origin of its principal host plant

• Crazy roots, hairy roots, crown gall

  change in the hormonal system of the plant resulting from the Rhizobium infection. Rhizobium rhizogenes puts a Ri-plasmid in the plant tissue and causes [...] overgrow the substrate and in severe epidemics the drippers get clogged. In tomato, excessive vegetative growth occurs. Life cycle and appearance of Crazy roots [...] Adjust the work order in greenhouses to fit with the hygiene protocol Disinfect the nutrient solution in order to prevent biofilm growth inside the irrigation

• Loose smut of barley

  cycle and appearance of Loose smut of barley The seeds are infected during flowering and the infected seeds are the primary source of inoculum in the next [...] next crop. The fungus survives inside the seed and when the seed germinates, the mycelium of the fungus grows upwards inside the plant into the growing tip [...] within a day and infect the inner tissues of the newly infected seed. During maturation of the seed, the mycelium becomes thick-walled and swollen as a

• Diamond back moth

  quite small and active. Except for the first instar, which mines in the leaf tissue, the larvae are voracious surface feeders. The pupae of the diamond back [...] toward the apex. The tips of the wings appear to turn upward slightly when viewed from the side. In males, the upper two-thirds of the forewings are dark [...] crevices near the bud. In cauliflower and broccoli, pupation may occur in the florets. Initially, the pupa is pinkish-white to pinkish-yellow and changes to

• Loose smut of wheat

  cycle and appearance of Loose smut of wheat The seeds are infected during flowering and the infected seeds are the primary source of inoculum in the next [...] next crop. The fungus survives inside the seed and when the seed germinates, the mycelium of the fungus grows upwards inside the plant into the growing tip [...] within a day and infect the inner tissues of the newly infected seed. During maturation of the seed, the mycelium becomes thick-walled and swollen as a

• 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 [...] wounds and by the infected leaves through the petioles. Fruits are infected through the flowers. The newly produced ascospores are dispersed by air and the [...] a cucumis in cucumber causes brown lesions on the foot and higher up on the stem. On the lesions, golden-brown gummy drops occur, hence the name gummy

• Horiver Wetstick

  s americanus Mode of action Insect pests are attracted to the colour of the sticky trap and get caught in the glue. Presentation Polysterene cards coated [...] wires or sticks at max. 30 cm above the crop and adjust height when plants are growing Do not place traps in-between the plants as parasitic wasps will then [...] 15-25 cm above the ground for young plants and 50 cm above the ground for mature plants Replace the traps when largely covered by insects and/or debris Dosage

• Brown root rot, corky root rot

  survives in the soil and in buried tomato roots as microsclerotia. The microsclerotia germinate and produce mycelium that in turn infect the roots of tomato [...] tomatoes and aubergine. It causes brown root rot and corky root rot. Damage symptoms The first signs of this disease, are poorly looking plants in localized [...] tomato and other hosts. Several alternate hosts in outdoor cropping systems are known: pepper, melon, aubergine, squash, spinach and safflower. The disease