%0 Journal Article %T Effects of bacterial isolate, Priestia megaterium HB8 and its filtrate on Controlling the root-knot nematode, Meloidogyne incognita %J Caspian Journal of Environmental Sciences %I University of Guilan %Z 1735-3033 %A Dawood, Hadeel Badri %A Malek Yass, Saad Tareq Abdul %D 2023 %\ 01/01/2023 %V 21 %N 1 %P 105-114 %! Effects of bacterial isolate, Priestia megaterium HB8 and its filtrate on Controlling the root-knot nematode, Meloidogyne incognita %K Priestia megaterium %K Root-knot nematode %K Meloidogyne incognita %R 10.22124/cjes.2023.6200 %X This study was conducted to isolate biological control agents from soil samples surrounding the roots of uninfected cucumber, watermelon, eggplant, tomato, and okra plants in fields infested with root-knot nematodes and to evaluate their effectiveness. Therefore, fifteen bacterial isolates were selected to study their effects on the vitality of the second stage juveniles (J2) of the root-knot nematode, Meloidogyne incognita. Nine bacterial isolates showed a mortality rate of juveniles ranged between 80 and 100%, while isolate HB8 was unique in having a high ability to influence the vitality of the juveniles, as the mortality rate reached 100%. This isolate was chosen to test its effectiveness in inhibiting egg hatching. The results showed that the inhibition rate after 72 h of incubation reached 94.33%. The effect of the bacterial filtrate of isolate Priestia megaterium HB8 was tested using three concentrations (10, 20, and 30%) on the mortality rate of J2 and the inhibition rate of egg hatching. Moreover, the 30% concentration exhibited a high ability to increase the mortality rate of a juvenile to 97.66% after 48 h of incubation, while the inhibition rate of egg hatching was 96.66% after 72 h. %U https://cjes.guilan.ac.ir/article_6200_4f3dbd2c26309e7a03c856cba2f183e3.pdf