Biocontrol Science and Technology (2011) 21, 509-521

Xiangxia Bu, Heng Jian, Zhongxiao Chen, Qiang He and Qian Liu (2011)
System optimization for attachment of Pasteuria penetrans to Meloidogyne incognita
Biocontrol Science and Technology 21 (5), 509-521
Abstract: For optimal mass production of Pasteuria penetrans in vivo, it is important to develop a system that can ensure 100% nematode attachment of the bacteria and high bacterial infection after inoculation. In this study, effects of endospore concentration and centrifugation parameters on attachment were investigated, followed by evaluation of impacts of centrifugation on endospore dislodgement, Meloidogyne incognita juvenile (J2) mortality, J2 infectivity, and bacterial infectivity. Endospore concentration and percentage of attachment fit well to mass-action and logit models, with the former being superior. Centrifugation had no impact on J2 mortality but had a great impact on endospore dislodgement in sand and water, nematode infectivity and bacterial infectivity. At nematode concentration of 2×10³ J2/mL, the optimal system for endospore attachment was developed which consisted of bacteria at 2×10⁴ endospores/mL, and centrifugation at 9000×g for 3 min three times. This system generated 100% attachment with approximately seven endospores/J2. After inoculation of treated nematodes to tomato plants, the inoculum yielded 47% bacterial infection, superior to 17% infection observed in centrifugation at 6000×g. Endospore dislodgement occurred after placing the centrifuged inoculated nematodes in sand or water for 24 and 48 h, which was more severe in centrifugation at 6000 than at 9000×g. Results also indicated that centrifugation led to lower nematode infectivity, regardless of endospore presence and centrifugation at 9000 or 6000×g, compared with the no centrifugation control.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Heng Jian

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
rearing/culturing/mass production
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Meloidogyne incognita
Pasteuria penetrans (antagonist)