EGGS DISTRIBUTION OF OLD WORLD BUG (DUBAS BUG) OMMATISSUS LYBICUS (DERBEG) ASCHE AND WILSON (HOMOPTERA: TROPIDUCHIDAE) ON FRONDS ROWS AND EFFECT OF DUST STORMS ON THREE VARIETIES OF DATE PALM TREES
Results of eggs distribution of Ommatissus lybicus on three varieties of date palm trees (Zahdi, Khustawi and Daery) indicated that Zahdi was the favorite variety for eggs laying in the field during three years between 2004 and 2006, while Daery was the less favorite one. The study also showed that the eggs distribution was different depending on fronds rows. The population density of average eggs ratios laid on 1st and 2nd frond rows were 64.3 and 64.4%, respectively, compared with 18.8 and 15.8% on the 4th and the 5th, and the average of eggs ratios decreased at the apex raws. The eggs population density of the second generation was higher than the first generation. There are significant differences in eggs distribution laid ratios between the 1st and the 2nd rows in 2004. The average eggs ratios were 5.8 and 3.3%, respectively, during 2005, while the ratios were 20, 17.4, 18.1, and 16.4% in the 5th, 6th, 7th, and 8th, respectively. The eggs distribution on frond rows were different with natural distribution, the results also showed that continuous occurrence of dust storms during June and July 2005 was a harmful factor causing reduction of means egg on the 1st and 2nd to about zero and 17.4, respectively, in the first generation during 2006, while the (4-8) front rows had 33.9, 27.3, 13.4, 2.2 and zero egg/leaflet in Iraq during June and July 2005 affecting the insect females which laid unfertilized eggs on fronds rows.
Jasim, H.K. and Al-Zubaidy, H.K. (2010). EGGS DISTRIBUTION OF OLD WORLD BUG (DUBAS BUG) OMMATISSUS LYBICUS (DERBEG) ASCHE AND WILSON (HOMOPTERA: TROPIDUCHIDAE) ON FRONDS ROWS AND EFFECT OF DUST STORMS ON THREE VARIETIES OF DATE PALM TREES . Acta Hortic. 882, 465-470