IMPACT OF SOME ABIOTIC FACTORS ON POPULATION FLUCTUATION OF WHITEFLY,  BEMISIA TABACI ( GENN.) AND POD BORER, HELICOVERPA ARMIGERA (HÜBNER)  INFESTING TWO TOMATO VARIETIES

Soliman, M. H. A.; Saad, Abla F. A.; Abozeid, Samia M.

doi:10.21608/mjapam.2017.126185

IMPACT OF SOME ABIOTIC FACTORS ON POPULATION FLUCTUATION OF WHITEFLY, BEMISIA TABACI ( GENN.) AND POD BORER, HELICOVERPA ARMIGERA (HÜBNER) INFESTING TWO TOMATO VARIETIES

Document Type : Original Article

Authors

Plant protection Research Institute, ARC, Doki, Giza, Egypt

10.21608/mjapam.2017.126185

Abstract

Weather factors plays a critical role in the population fluctuation of certain insects infesting tomato in field. Whitefly, Bemisia tabaci ( Genn.) ( Homoptera : Alyrodidae ) , pod borer, Helicoverpa armigera (Lepidoptera: Noctuidae) infesting tomato foliage and fruits and considered the most serious pests infesting tomato plantation all over the world. This research was conducted to study the effect of air temperatures , relative humidity and dew point on population fluctuation of Bemisia tabaci and Helicoverpa armigera, eggs and larvae at different examination dates. The field experiment were carried out in a private farm of Elghaba village , Abukabier district , Sharkia governorate, along two successive summer plantations 2014 and 2015. Experimental area was planted with tomato , Lycopersicon esculentum ( Mill.) Super Strain B (SSB) and Castle rock (CR) varieties. The obtained results show that there were significant differences and positive correlation between air temperature , relative humidity & dew point and eggs and larvae number of Bemisia tabaci and Helicoverpa armigera along the two successive seasons (2014 and 2015). Air temperature , relative humidity and dew point affect egg and larvae numbers of both studied insects by 16.7 to 82.6 % and 1.2 to 69.8% during 2014 and 2015,respectively. Bemisia tabaci recorded three peaks on castle rock ( CR ) and super strain B ( SSB ) recorded ( 30,300 and 140 eggs/ ten leaves ) and (40, 32 and 20 eggs/ ten leaves ) at 13^th May , 10^th and 30^th June , while H. armigera recorded one peak on both varieties during 10^th June 2014 recorded 107 and 32 eggs/ ten leaves , respectively on CR and SSB. Also, the results indicated that B. tabaci and H. armigera larvae population during 2014 summer season recorded three peaks on CR and SSB , during 20^th May, 10^th June and 6^th July 2014 . At 2015 summer season the results revealed that population fluctuation of B. tabaci and H. armigera eggs recorded one peak on both varieties , expect B. tabaci egg on CR which recorded two peaks ( 15, 3 egg / 10 leaves ) at 13^th May and 3^rd June. Regarding to larvae population of B. tabaci on SSB , there were three peaks , but larvae population of B. tabaci on CR , H. armigera on SSB and CR recorded two peaks.

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