Periodic viڑits covered sugarcane plantations at Attfeih
district (Gيa Governorate) during 2008 and 2009 seasons
for surveying parasitoids of sugarcane soft sca/e, Pu/vinaria
tenuivalvata. Data confirmed that the apheilnid parasitoid,
Coccophagus scutellaris is the main parasitoid as ،t played a
natural . active ro/e against this pest in nature. Results
proved that a number of one to ten parasitoid adults
emerged from a single host depending upon the age of the
host. The second nymphal instar was the highest preferred
for parasitism (96%), while the mature females were the
lowest (57%) parasitism. The mean seasonal rate of
parasitism was hi’her in 2009 (46. 35%) than 2008
(41.05%), thus indicating that C. scutellaris played oaturally
an important role in reducing the population of the pest in
sugarcane plantations at Attfeih district. Also, a field
experiment was conducted atn Al-Rawda village (Mm/a
Governorate) during the same seasons (2008 and 2009) in
order to increase the proportion of parasitism in P.
tenuivalvata infesting sugarcane plantations. Pa ras/ti ed
soft scales were collected from heavily infested sugarcauie
fields to be released in the area of experiment at a rate of 3
parasitized scales/p/ant. Re/easing led to increases in the
number of parasitized soft scales and the percentage of
parasitism by 170 and 117%, respectively ،n 2008 and
163. .1 and 139.8%, respectively in 2009 sugarcane season.
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