Tobacco aphid

through the crop by walking. The tobacco aphid tends to form denser colonies, closer to the top of the plant, than the peach potato aphid . It is not known [...] from the plant and disturb the balance of growth hormones. As a result, the plant’s growth is retarded giving rise to deformed leaves or, if the infestation [...] therefore need to extract large quantities of sap to get sufficient protein. The excess sugar is secreted in the form of honeydew, making the crop and its

Diamond back moth

may occur in the florets. Initially, the pupa is pinkish-white to pinkish-yellow and changes to brown before adult emergence. The adult of the diamond back [...] xylostella) is slender, greyish brown with pronounced antennae. The hindwings are narrow, pointed toward the apex. The tips of the wings appear to turn upward [...] are like those of the males. The back is marked with a broad cream or light brown band along the back, which is sometimes constricted to form one or more

Beet armyworm

es for the growth of the crop. With a substantial population of caterpillars, the damage can spread to the stems, and in the worst cases to the fruit. [...] plants. In both the greenhouse and the field, it is a major pest of sweet pepper. Damage symptoms Older caterpillars migrate to the top of the plant where [...] even black. The colour and pattern of the caterpillars is highly variable and depends partly on the host plant, the stage of development and the climate.

Fusarium wilt

Fusarium oxysporum is the only Fusarium that actually grows inside the vessel system of the host plant and spreads upwards inside the plants. The other species [...] Fusarium oxysporum is the species causing vascular wilt. First the leaves turn yellow and wilt, mostly on one side of the plant. Finally, the whole plant wilts [...] upwards on the outside of the plant. Most Fusarium species only make asexual spores. Some also produce ascospores. The Fusarium oxysporum life cycle, is similar

Pea blight, leaf and pod spot

and surrounded by a dark brown to red-brown border. The first infection is often on the primary leaves. The fungus is seed borne and thus also causes post- [...] transmitted on the outside of the seed coat and cause primary infection. The conidia germinate and infect through the stomata or directly through the cuticle [...] on leaves, stems and pods of peas. The spots on leaves and pods are round, on the stems they are more elongated. The lesions are light brown, sunken and

Cutworms

into the growing stalk, disrupting the sap flow in the plant. Life cycle and appearance of Cutworms The adults of Agrotis spp. have pale grey to grey-brown [...] a broad dark marginal stripe. The wingspan is about 40-55 mm and the dorsal thorax is covered with close-lying hairs. The eggs are white at first but rapidly [...] eggs. There are six to seven larval stages. Pupation takes place in the ground. Depending on the temperature, the development from egg to adult takes about

Tomato

About The tomato plant ( Solanum lycopersicum) belongs to the nightshade family of Solanaceae . The tomato is the edible fruit of this plant. The plant [...] plant is native to Central and South America and the tropical highlands. Tomato plants usually grow to a height of between 1-3 metres (or 3-10 feet). Their [...] Their stem is not so strong, so if not supported (like in a greenhouse) the stem often extends over the ground. Indeterminate tomato types are so-called ‘tender’

Tomato leaf miner

roughly one hour the larva crawls out of the leaf and falls to the ground. This occurs in the early morning. The larva crawls into the ground to pupate. A small [...] head. When the larva hatches from the egg, it begins to eat into the leaf at once, tunnelling down into the mesophyll tissue where damage is caused by extensive [...] both directly and indirectly. The most direct damage is caused by the larvae mining the leaf tissue, leading to desiccation, premature leaf-fall and cosmetic

Gummy stem blight

be recognized from the outside by the small narrowing of the tip of the mature fruits. The symptoms on stems, leaves and inside the fruits may occur together [...] higher up on the stem. On the lesions, golden-brown gummy drops occur, hence the name gummy stem blight. On the lesions, black specks, the new fruiting [...] ascospores are the main source of dispersal of disease upwards in the crop and the conidia for spread of the disease downwards. How to prevent Gummy stem blight

Guava

– a smallish tree. The pulp varies from off-white to bright pink, and is between 4 to 12 cm in length. The taste ranges from tart to very sweet. [...] tropical fruit is cultivated in many tropical and subtropical regions. A vivid yellow or green on the outside, Psidium guaiava, is the fruit of the Myrtle family