Study the population fluctuation of the red palm weevil rhynchophorus ferruginous in two different Egyptian regions

الملخص EN

The population fluctuation of the red palm weevil, R.

ferrugineus was studied, using the aggregation pheromone traps, during 2016/2017 and 2017/2018 in two different regions of Egypt as follows: a- Alexandria Governorate: The population of R.

ferrugineus attracting to the trap number 1, increased gradually from mid of July 2016 (7individuals) to reach its peak in mid of September (26individuals), and then decrease to reach the lowest level of abundance at middle of January 2017 (2insect only).

Also, there was another peak of R.

ferrugineus noticed during beginning of July 2017 (26insects).

The attracting insects to the trap 2 had the same trend in the previously mentioned trap, as the highest population of the insects was noticed during the middle of September 2016 recording 32 insects, but the lowest population of collected insect was observed during the end of January 2017.

The males in the tested traps were disappeared during the period from the end of January to the middle of February 2017.

The highest number of attracted R.

ferrugineusat Alexandria was recorded during 13/9/2017 in the first trap (22insects), but the second trap had attracted the highest number of insects at the same investigation time as (30insects).

The period of end of January 2018 to the middle of February was avoiding the appearance of insects in the first trap but in the second trap, the insects disappeared during the period of 3/1/2018 till 14/2/2018 forb- El-Beihera region: The sampling date 9/10/2016 harbored the highest population of both males and females of R.

ferrugineus in El- Behira in the first trap.

In the second trap the highly abundance of weevil for the sampling date 11/4/2017 (38 insects).

Also, the study showed that the number of females was higher than the males in most cases.

The highest population was recorded during 9/10/2017 in the first trap (33individuals), but the date 11/4/2018 showed the highest R.

ferrugineus abundance in the second trap (34insects).

The current study indicated that there were highly significant differences between the total number of males and the regions, but there was no any effect of seasons separately on this population in the trap 1.

Also, the interaction between the regions and study seasons had no any effect on the male's populations.

There were no any effects for regions and study seasons on the population of R.

ferrugineus inside the trap number 2.

In trap 1, there were positive correlations between the effect of females and temperature on the population of the males.

Also, the same correlations were observed for effect of males and temperatures on the population of female populations.

However, the effect of relative humidity factor on the population of male and females was negative effect in both tested traps.

The study indicated that El-Behira region harbored more R.

ferrugineus than Alexandria during the two study seasons.

The average insects were 4.615 and 3.653 insects in Alexandria and 6.5 and 5.57 in El-Behira, during the two seasons, respectively.