Bulletin of the National Research Centre (Oct 2019)

Application of Bacillus species for controlling root-knot nematode Meloidogyne incognita in eggplant

  • Wafaa M. A. El-Nagdi,
  • Hassan Abd-El-Khair

DOI
https://doi.org/10.1186/s42269-019-0187-6
Journal volume & issue
Vol. 43, no. 1
pp. 1 – 10

Abstract

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Abstract Background Eggplant (Solanum melongena L.) is one of the important vegetable crops infected by Meloidogyne incognita all over the world, including Egypt. Chemical nematicides frequently cause environmental pollution and toxic hazards to human, plants, and animals; certain biocontrol agents that are environmentally friendly and safe to humans and animals were tested against the root-knot nematode Meloidogyne incognita in eggplant. Objective This work is aimed to determine the nematicidal activity of Bacillus spp., viz., B. subtilis and B. pumilus, against M. incognita in three separated experiments to study their ability in controlling M. incognita and in improving the growth parameters of eggplants. Bacillus spp. were applied as single or in combination (experiment I), single treatment at different doses (experiment II), and different times (three times) of application (experiment III). Results The results of experiment I revealed that Bacillus sp. + B. subtilis significantly reduced the second-stage juvenile (J2) in soil and galls and egg masses in roots, while Bacillus sp. + B. pumilus significantly reduced J2 in roots. Bacillus spp. in pairs were more effective against M. incognita. In experiment II, Bacillus sp. (40 ml) significantly reduced the J2 in soil and galls and egg masses in roots, while B. pumilus (40 ml) significantly reduced the J2 in roots. The nematicidal activity of Bacillus spp. was increased by increasing the applied dose. In experiment III, B. subtilis, when applied three times, significantly reduced the J2 in soil and the J2 and galls in roots, while B. pumilus (applied three times) significantly reduced the egg masses in roots. All Bacillus spp. treatments highly increased the tested growth parameters compared to the controls. Conclusions The tested biocontrol agents used more than once or in combination are more effective than those used only once in controlling nematode parameters in eggplant under greenhouse conditions with a consequent increase in eggplant growth. These bacterial isolates need to be studied under different field conditions for confirmation.

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