This research carried out in the orchards of the Stamo area province of Lattakia citrus
during the years 2014-2015, and the results of the study showed that the insect black
cortical one generation per year with a second partial generation during t
he summer. Under
the insect overwintering nymph stage in the second age is the most able to withstand the
low-temperature phase in the winter. Mermaid back age-second activity in the beginning of
spring to complete their life cycle where the female young appear in early April on each of
the branches and leaves, to show adult females with the beginning of the month of May
and starts the eggs to hatch in the middle of this month and will continue until the month of
July. The study found that the nymph stage second phase age is the most common during
the season at each of the branches and leaves. Observed the death of large numbers of the
insect in the phasic nymph third age and female fledgling stage, which evolved during the
same season, as the study of the distribution and the spread of the different phases of the
insect on the plant parts showed that the branches were more injury than securities with
higher than moral in the population density of the presence of eccentric nymph and adult
stages the branches compared with the leaves.
The effect of temperature on the development of the predator Hippodamia variegata
(Coleoptera:Coccinellidae) reared on the green peach aphid Myzus persicae Sulzer
(Homoptera:Aphididae) was determined at five constant temperatures (15, 20, 25, 30
a
nd 35)°C under laboratory conditions. The present study was conducted at Latakia
Agricultural Research Center during 2015 and 2016. This study aimed to determine
the impact of temperature on the development of the predator H. variegata to
identify the suitable temperature for rearing this predator. The duration (days) and
survival (%) were measured for this predator. Results showed that temperature had
a significant effect on the development of H. variegata immature stages, whereas
the development time from larvae to adult decreased with increasing temperature
at thermal range (15-35)°C. The longest larval developmental duration was 24.84 days
at 15°C, and the shortest duration was 4 days at 35°C. Also, the shortest pupal
duration was one day at 35°C and the longest period was 9.84 days at 15°C. The
lowest developmental time from eggs hatching to emergence of adults was 6 days
at 35°C, while the longest developmental time was 36.84 days at 15°C. Also the
ratio of larval survival was affected by temperature, this ratio was (26%, 52%,
77%, 34%, 4%) at (15, 20, 25, 30 and 35)°C respectively. The results of statistical
analysis showed that there were significant differences between the five constant
temperatures in all studied biological characteristics, and the temperature 25°C was
suitable for a successful rearing of the predator H. variegata.
