دراسة أولية لتحديد نسبة و شدة الإصابة بخنافس الأوراق (Coleoptera : Chrysomelidae)‎ في موقعين لزراعة الشوندر السكري البنجر في محافظة حمص في سورية

الملخص EN

The study was conducted in two different regions (Al-Rasten and Quatena) in Homs during 2007 and 2008 growing seasons.

The main objective of this study was to determine the damage rate and severity caused by the sugar beet flea beetles (Coleoptera: Chrysomelidae) in the two regions.

The results showed that the damage rate was significantly higher in Quatena than in AL-Rasten during the two seasons.

The mean damage rate was 54.90% and 36.06 in Quatena during the whole two seasons, respectively, and 34.50% and 29.79% in AL-Rasten during the whole two seasons, respectively.

Early in the season the mean damage rate was 58.30% and 26.50% in Quatena, and 30.20% and 3.10% in Al-Rasten during the two seasons, respectively.

On the other hand, there was significant difference in the severity of injury between the two regions based on the methods used; the hole count method and the injury leaf area method.

By using the hole count method, 90.67% of sugar beet plants were with low severity, and 9.43% of plants with medium severity in Al-Rasten region during 2007, whereas 94.67-100% of the plants were with low severity in 2008.

In the Quatena region, 37.33% to 58.67% of sugar beet plants were with low severity, 38.67% to 53.33% of plants with medium severity and 2.66% to 9.33% with high severity during first season (2007), whereas 14.67% of the plants were with high severity, 56% with medium severity and 29.33% with low severity during 2008 growing season.

Results showed significant difference between Gatena on Al-Rasten at P= 0.05.

The mean severity level was 2.4% and 14.4% in Al-Rasten and Gatena during 2007, respectively, whereas it was 2.07% in Al-Rasten and 4.47% in Quatena during 2008.

Early planting permitted escape from injury in Al-Rasten region.