Diadegma aegyptiator Shaumer 1966 (Hymenoptera: Ichneumonidae): New Record Parasitoid on the Rib Miner, Scrobipalpa ocellatella Boyd. (Lepidoptera: Gelechiidae) in Egyptian Sugar Beet Fields

Abstract

The larvae of the rib miner,Scrobipalpa ocellatella Boyd feed on the sugar beet leaves and roots causing huge damage in such a way that the root rot and thus it caused a reduction in the yield of roots and the sugar content in the roots. Parasitoids are the most effective natural enemies for insect biological control. In nature, several parasitoids were observed to be potential bio-agents of serious crop pests. The future of "insecticide-less" pest management will be driven by a bouquet of parasitoids and predators complimented by entomopathogens. The reduction in insecticide residues in food -sugar beet is a food crop -is desirable for public health. The present study was carried out at the experimental farm of Sakha Agricultural Research Station, Kafr El-Sheikh Governorate-Egypt throughout two successive seasons 2018/2019 and 2019/2020. New parasitoid was recorded from the rib miner pupae. It was identified as Diadegma aegyptiator on S.ocellatella for the first time in Egypt. The Overall of parasitism were 24.52 and 31.03% in the two seasons, respectively. As well as, statistical analysis proved that a highly positive significant correlation coefficient values between S.ocellatella and its parasitoid in two seasons, respectively.These results elucidate that this parasitoid is a promising tool in reducing S.ocellatella populations.

Role of Parasitoid Species and Insecticides in Controlling Populations of Beet Moth in Sugar Beet Fields

“…In another study, Bazazo and Ibrahim (2019) calculated the mean of parasitism of D. oranginator on S. Ocellatella was 55.17, 60.46 and 68.91% for the three cultivations, respectively. In addition, Bazazo and Hassan (2021) monitored the overall parasitism to D. aegyptiator on S. Ocellatella larvae with 24.52 and 31.03% during the two seasons, respectively. these findings demonstrated that these parasitoids complex of S. ocellatella are able to manage this dangerous insect pest.…”

“…In addition, Bazazo and Ibrahim (2019) estimated the parasitism rates by Diadegma oranginator Aub to be 55.17, 60.46 and 68.91% for three cultivations, respectively. Further, mean parasitism by Diadegma aegyptiator Shaumer on S. ocellatella larvae ranged from 24.52 to 31.03% in the first and second seasons, respectively (Bazazo and Hassan, 2021).…”