- The scientific name : Clinodiplosis oleisuga
- the family :Diptera
- Symptoms of the disease :
- Many holes in the plant branches
- The branches in the affected area are colored purple from the outside.
- Dry branches.
- Description of the insect:
The length of the insect is (5 mm) and the antennae are knobby. The body color is yellow, covered with scattered cilia. On both sides of each abdominal ring is a dark yellow spot. The larvae (3 mm) are legless and are red in color at the beginning of life and yellow in the last larval stage. The pupa is barrel-coloured. orange .
- The causes of disease :
Climate changes due to global warming are the reason for its outbreak and spread on olives
- Conditions suitable for the spread of the disease :
Climatic conditions are favorable for its spread, such as high air humidity and moderate temperature almost throughout the year
Female fertility increases during the fall months; In the summer months, its fertility reaches its lowest level
- Disease development cycle :
- Adults continue to be present and lay eggs from April to October, and two main flight peaks are usually observed: the first in July and the second in September. The life cycle and overall larval behavior are strongly influenced by climatic conditions. During the spring and summer period, it completes the part of its life cycle (from egg to adult) in 35-50 days. Thus, between April and October, three or four overlapping generations can occur.
- The female uses any break in the bark in branches 3-15 mm in diameter to lay eggs, but in the nursery pruning cuts from the side branches of young trees are the most common sites for laying eggs. As a result of the development of larval populations in the open gallery between the bark and the central cylinder, and the associated development of the fungus Libertella sp. (Xylariales: Diatrypaceae), the wood of the affected area dries up and deteriorates.
- Losses from the spread of the disease:
In many plants the total loss reaches 10-15%.
- The infection results in the fall of the affected fruits before they ripen, especially in the months of September and October. The percentage of oil in the affected fruits decreases and their acidity increases.
- Control strategy
- Preventive measures to prevent the occurrence of the disease
- Deep plowing of the land under the olive trees, after collecting the crop
- Treating wounds on the branches and pruning them to avoid the formation of wounds resulting from close branches rubbing against each other when moved by the wind.
- Cut the affected branches and burn them
- Chemical and organic control recommendations
- The inland location of the larval population, the microclimatic conditions favorable to incubation, and the succession of several generations overlapping during the year, make this species particularly difficult to control by insecticide treatments. These difficulties are compounded by the lack of approved pesticides for this specific problem. For these reasons, it is believed that the most appropriate nursery approach to reducing damage caused by midge infestation is to prevent egg laying and manage pruning cuttings properly.
- Light and pheromone traps, especially in July
- Possible chemical treatment with dimethoate.
- References
- Samara, R., Alkowni, R., AbuQauod, H., & Jarrar, S. (2016). Reporting Olive bark midge Resseliella oleisuga Targ.(Diptera: Cecidomyiidae) infesting olive trees in North Palestine. The Third International Conference on Olives in Palestine (ICOP 3rd). PTUK...
- BAGNOLI, B., et al. Impact of Resseliella oleisuga infestation on young trees in Tuscan nurseries (Diptera: Cecidomyiidae). Comptes rendus de la réunion, 2014, 108: 16.
- Links :
https://scholar.ptuk.edu.ps/handle/123456789/352
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1439-0418.1979.tb02480.x
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