Tamarixia radiata Behaviour is Influenced by Volatiles from Both Plants and Diaphorina citri Nymphs

Tamarixia radiata (Waterston) is an important ectoparasitoid of the Asian citrus psyllid, Diaphorina citri Kuwayama, a globally destructive pest of citrus. In the present study, a Y-tube olfactometer was employed to investigate whether the parasitoid T. radiata is capable of utilizing the odour source emitted by both plants and insect hosts during its foraging. The odour sources included Murraya paniculata (L.) shoots, 1st, 2nd, 3rd, 4th, and 5th D. citri instar nymphs, both individually and in combinations. Moreover, nymph-stage choice for parasitism, including 3rd, 4th, and 5th D. citri instar nymphs, was carried out. The results indicated that female T. radiata were only significantly attracted to volatiles emitted by M. paniculata shoots, 3rd, 4th, and 5th instar nymphs of D. citri, but could not distinguish between them. T. radiata males were not attracted by odours sourced from any instar D. citri nymphs. Female T. radiata adults exhibited a significant preference to later instar nymphal stages of D. citri for oviposition. The results from this study can be used to guide further investigations on the searching behaviour of this parasitoid and its utilization in D. citri biocontrol.

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Titers of ‘Ca. Liberibacter asiaticus’ in Murraya paniculata and Murraya-reared Diaphorina citri Are Much Lower than in Citrus and Citrus-reared Psyllids

HortScience ◽

10.21273/hortsci.47.10.1449 ◽

2012 ◽

Vol 47 (10) ◽

pp. 1449-1452 ◽

Cited By ~ 12

Author(s):

Abigail J. Walter ◽

YongPing Duan ◽

David G. Hall

Keyword(s):

North America ◽

Citrus Sinensis ◽

Ornamental Plant ◽

Asian Citrus Psyllid ◽

Diaphorina Citri ◽

Alternate Host ◽

Murraya Paniculata ◽

Liberibacter Asiaticus ◽

Laboratory Colonies

Huanglongbing, one of the most devastating diseases of citrus, is associated with the bacterium ‘Candidatus Liberibacter asiaticus’ vectored by the Asian citrus psyllid, Diaphorina citri, in North America. Murraya paniculata is a common ornamental plant that is an alternate host of both the psyllid and bacterium. We tested M. paniculata and Citrus sinensis grown together in the same field for their titer of ‘Ca. L. asiaticus’. We found the bacterium in both M. paniculata and C. sinensis, but the titer was four orders of magnitude lower in M. paniculata. We also assayed D. citri from laboratory colonies reared on either ‘Ca. L. asiaticus’-infected M. paniculata or infected Citrus spp. Psyllids reared on infected M. paniculata also carried bacterial titers five orders of magnitude lower than psyllids reared on infected Citrus spp. These observations imply resistance to huanglongbing in M. paniculata.

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Knockdown of calreticulin, laccase, and Snf7 Genes Through RNAi Is Not Effective to Control the Asian Citrus Psyllid (Hemiptera: Livideae)

Journal of Economic Entomology ◽

10.1093/jee/toaa240 ◽

2020 ◽

Vol 113 (6) ◽

pp. 2931-2940

Author(s):

Jéssika Angelotti-Mendonça ◽

Meire M Bassan ◽

João Paulo R Marques ◽

Pedro T Yamamoto ◽

Antonio Figueira ◽

...

Keyword(s):

Target Gene ◽

Target Genes ◽

Asian Citrus Psyllid ◽

Diaphorina Citri ◽

Transcript Accumulation ◽

Citrus Industry ◽

Murraya Paniculata ◽

Knockdown Effect ◽

Detached Leaves ◽

Candidatus Liberibacter

Abstract The Asian citrus psyllid, Diaphorina citri Kuwayama, transmits the bacteria Candidatus Liberibacter associated with huanglongbing (HLB), a devastating disease of the citrus industry. The use of genetically modified plants is an alternative to control this vector. Conversely, technology based on RNA interference (RNAi) for silencing specific genes of a target insect could be attempted. This work evaluated the knockdown effect of the target genes calreticulin (DcCRT), laccase (DcLAC), and Snf7 (DcSnf7) by RNAi through feeding D. citri in Murraya paniculata leaves after the uptake of an aqueous solution with dsRNA homologous to each vector target gene. Confocal microscopy revealed the uptake of the fluorescent-labeled dsRNA by detached leaves and the symplastic movement, allowing the ingestion by the feeding insect. A reduction in the survival rate was observed only 144 h after the beginning of feeding with dsRNA targeting DcSnf7; however, no reduction in transcript accumulation. The knockdown of the DcCRT and DcLAC genes was detected only 12 and 96 h after insect feeding, respectively. Additionally, a reduction in amino acid excretion from insects fed with dsRNA targets to DcCRT and DcLAC was observed 120 h after the beginning of feeding. However, the effects of the dsRNAs tested here appear to be minimal, both at the transcriptional and phenotype levels. For most concentrations and time points, no effects were observed. Therefore, the knockdown of genes DcCRT, DcLAC, and DcSnf7 do not appear to have the potential to control of D. citri through RNAi-mediated gene silencing.

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Preference of Adult Asian Citrus Psyllid, Diaphorina citri (Homoptera: Psyllidae) for Murraya paniculata and Citrus unshiu

Japanese Journal of Applied Entomology and Zoology ◽

10.1303/jjaez.2008.27 ◽

2008 ◽

Vol 52 (1) ◽

pp. 27-30 ◽

Cited By ~ 10

Author(s):

Kousuke Ikeda ◽

Wataru Ashihara

Keyword(s):

Asian Citrus Psyllid ◽

Citrus Unshiu ◽

Diaphorina Citri ◽

Murraya Paniculata

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Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), a small but voracious predator of Diaphorina citri Kuwayama (Hemiptera: Liviidae)

ACTA ZOOLÓGICA MEXICANA (N S ) ◽

10.21829/azm.2018.3412127 ◽

2018 ◽

Vol 34 (1) ◽

pp. 1-5

Author(s):

Takumasa Kondo ◽

Angela María Arcila ◽

Laura Isabel Colorado ◽

Yenifer Campos-Patiño ◽

Paola Sotelo-Cardona

Keyword(s):

Adult Stage ◽

Fire Ant ◽

Asian Citrus Psyllid ◽

Exposure Control ◽

Diaphorina Citri ◽

Experimental Conditions ◽

Exact Test ◽

Wasmannia Auropunctata ◽

Murraya Paniculata ◽

Little Fire Ant

The effect of predation by the little fire ant Wasmannia auropuntacta (Roger) (Hymenoptera: Formicidae) on Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae) kept under experimental conditions for the breeding of the parasitoid Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) was evaluated. An experiment was carried out using cages with capacity for 9 plants of Murraya paniculata (L.) Jack (Rutaceae) infested with an average of 600 nymphs of D. citri and 100 adults of T. radiata per cage. Three cages were exposed to ants and one had no ant exposure (Control). In each cage, the numbers of healthy and parasitized nymphs and the numbers of adults of D. citri and T. radiata were counted every 2 days for 15 days. Exposure to predation by W. auropunctata significantly affected the number of nymphs that reached the adult stage as well as the number of nymphs parasitized by T. radiata (Fisher's exact test). In the ant-exposed cages, about 3% of the nymphs survived to the adult stage in contrast to 18% in the control cage. Likewise, the action of the parasitoid was affected, with 24% of nymphs parasitized in the ant-exposed cages in contrast to 66% in the control cage. Wasmannia auropunctata has a great potential as a natural enemy of this psyllid pest in citrus nurseries. The ant also consumes T. radiata by consuming parasitized nymphs of D. citri and this predation may negatively impact the control of D. citri by the parasitoid.

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