Impact of certain pests on the response and productivity of okra cultivars in Sohag governorate

الملخص EN

The present work was conducted at Shandweel Agricultural Research Station, Sohag Governorate during 2017 and 2018 okra growing seasons to determine the population trends and susceptibility degrees against the prevalent sap sucking arthropod pests inhabiting 4 okra cultivars.

Aphis gossypii Glover (Hemiptera: Aphididae) , Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Empoasca discipiens (Paoli) (Hemiptera: Cicadellidae) and Tetranychus urticae Koch.

(Acari:Tetranychidae) were found to be the most dominant species on the tested okra cultivars.

The highest populations of A.

gossypii, E.

discipiens and T.

urticae were recorded during July, however, the highest populations of B.

tabaci mature and immature stages were recorded during May and June.

The tested okra cultivars showed varied susceptibility degrees against the studied pests.

Except of, A.

gossypii, white velvet okra cultivar showed some sort of resistance against B.

tabaci, E.

discipiens and T.

urticae.

It must be shed a light on the presentation of A.

gossypii at obvious low numbers on balady green cultivar which showed some sort of resistance against this destructive insect pest.

Under sprayed and unsprayed procedures, influence of the pest's infestation on some yielding characters was studied.

Okra cultivars varied significantly in both seasons.

Under natural infestation, the yield and great proportion of the yield components decreased significantly compared to managed infestation.

golden coast okra cultivar gave the highest fresh fruit yield per feddan and followed by white velvet okra cultivar.

Both cultivars harbored moderate levels of the above mentioned pests.

However, white velvet recorded the lowest reduction for fresh fruit yield per feddan and followed by golden coast.

So, it can be recommended using the later cultivars as a part of an integrated pest management program.

Furthermore, these results could be helpful for varieties screening programs.