Pest



Spider mites
 
                                                       Damage by spider mites

Spider mites are common pest problems on many plants around yards and gardens. The most important spider mite is the two spotted spider mite (Tetranychus urticae). Injury is caused as they feed. Damaged areas typically appear white flecks.Following severe infestations, leaves become discolored, scorched and drop prematurely.
      Many spider mites produce webbing, particularly when they occur in high populations. This webbing gives the mites and their eggs some protection from natural enemies and pesticides.
Spider mites develop from eggs. After hatching, the old egg shells remain and can be useful in diagnosing spider mite problems.
     Most spider mite activity peaks during the warmer months, especially, as well as in dry conditions. They can develop rapidly during this time, becoming full-grown in as little as a week. After mating, mature females may produce a 12-15 eggs daily in 2 weeks. The fast development rate and high egg production enable it extremely rapid increases its populations.


whitefly
 Damage by whitlfy
 
The whitefly’s nymphs feed on plant juice and excreted sticky honeydew. The honeydew improves the growth of moulds, which interferes in the photosynthesis and transpiration of the plant. Furthermore, whiteflies are true vectors of many viruses such as TYLCV.
     Amblyseius swirskii especially prefer the eggs and first nymph stage of greenhouse whitefly or tobacco whitefly. It can consume about 10 eggs and young larvae in a day.

Thrips


Damage by thrips
 
Thrips can injure many crops with different ways. The injured leaves show a grey or silver color by the feeding of thrips. In addition, thrips excrements can lower the value of ornamental crops. Thrips eggs are laid in the leaf tissue and can cause warty suberizations. In different crops, deformations and discolorations of the leaf, fruit and flowers can be detected. Thrips are also known vectors of many viruses.
         Amblyseius swirskii mainly prey on the young larvae of thrips. Its efficiency of biocontrol for thrips is better than that of Amblyseius cucumeris which means that about 5 larvae are      consumed in a day.

Broad mite

 
 
Damage by broad mite
 
The broad mite, Polyphagotarsonemus latus, has a large host range world-wide and a world-wide distribution. It has four stages in its life cycle: egg, larva, nymph and adult. There are also reports of the broad mite using insect hosts, specifically some whiteflies species, to move from plant to plant (Palevsky et al. 2001).
     This destructive pest causes terminal leaves and flower buds to become malformed. The mite's toxic saliva causes twisted, hardened and distorted growth in the terminal of the plant. Mites are usually seen on the newest leaves and small fruit. Leaves turn downward and turn coppery or purplish. Internodes shorten and the lateral buds break more than normal. The blooms abort and plant growth is stunted when large populations are present. On fruit trees the damage is usually seen on the shaded side of the fruit, so it is not readily apparent. Fruit is discolored by feeding and in severe cases premature fruit drop may occur. Severely damage fruit or eggplant is not salable in the fresh market but may be used for processing.
 

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