University of Guilan Plant Pest Research 2538-6123 8 4 2019 02 20 Effect of sugar concentration and feeding duration on the cold tolerance of Bracon hebetor Say adults Effect of sugar concentration and feeding duration on the cold tolerance of Bracon hebetor Say adults 55 69 3306 10.22124/iprj.2019.3306 FA A. Afshari Department of Plant Protection, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran E. Nazari Fandokht Department of Plant Protection, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Journal Article 2019 03 13 Cold storage is a general technique to long-term preservation of wasp parasitoid, Bracon hebetor in insectaries. The aim of this study was to investigate effects of honey solution concentration (5, 20 and 40%) and feeding duration (24, 48 and 72 hours) on the biological and reproductive characteristics of this parasitoidin both cold-stored and not-stored conditions. Adult parasitoids collected immediately after emergence and stored inside a refrigerator (5±1˚C) for 7 days, and mortality, longevity, fecundity and parasitism ability were subsequently assessed. In unstored populations, parasitoid longevity, fecundity and parasitism ability increased by sugar concentration and reached to their peaks in 40% honey solution (17.8±1.4 days, 230.3±12.1 eggs/female and 140.3±8.6 host larvae/ female, respectively). Moreover, sugar concentration and feeding duration significantly affected cold stored parasitoids quality. Adults feeding on high concentration of honey solution (40%), increased significantly their cold tolerance and longevity and fecundity after cold storage. 24-hour feeding on 40% honey solution before cold storage was the best treatment to keep parasitoid quality during cold storage. In this case, female longevity, fecundity and parasitism ability were estimated 22.9±2.1 days, 330.9±46.4 eggs/female and 173.3±18.1 host larvae/female, respectively. In conclusion, it seems that feeding wasps with a 40% honey solution for 24 hours before cold storage could be recommended to increase cold tolerance of adult B. hebetor. Cold storage is a general technique to long-term preservation of wasp parasitoid, Bracon hebetor in insectaries. The aim of this study was to investigate effects of honey solution concentration (5, 20 and 40%) and feeding duration (24, 48 and 72 hours) on the biological and reproductive characteristics of this parasitoidin both cold-stored and not-stored conditions. Adult parasitoids collected immediately after emergence and stored inside a refrigerator (5±1˚C) for 7 days, and mortality, longevity, fecundity and parasitism ability were subsequently assessed. In unstored populations, parasitoid longevity, fecundity and parasitism ability increased by sugar concentration and reached to their peaks in 40% honey solution (17.8±1.4 days, 230.3±12.1 eggs/female and 140.3±8.6 host larvae/ female, respectively). Moreover, sugar concentration and feeding duration significantly affected cold stored parasitoids quality. Adults feeding on high concentration of honey solution (40%), increased significantly their cold tolerance and longevity and fecundity after cold storage. 24-hour feeding on 40% honey solution before cold storage was the best treatment to keep parasitoid quality during cold storage. In this case, female longevity, fecundity and parasitism ability were estimated 22.9±2.1 days, 330.9±46.4 eggs/female and 173.3±18.1 host larvae/female, respectively. In conclusion, it seems that feeding wasps with a 40% honey solution for 24 hours before cold storage could be recommended to increase cold tolerance of adult B. hebetor.

https://iprj.guilan.ac.ir/article_3306_b581f4b507e35fc4215aa52aff5490b3.pdf