Skip to main content
ARS Home » Research » Publications at this Location » Publication #264990
Title: Colonization of citrus and citrus-related germplasm by Diaphorina citri (Hemiptera: Psyllidae)

Author
item WESTBROOK, CATHERINE - Former ARS Employee
item Hall, David
item Stover, Eddie
item Duan, Ping
item Lee, Richard

Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/3/2011
Publication Date: 7/15/2011
Citation: Westbrook, C.J., Hall, D.G., Stover, E., Duan, Y.P., Lee, R.F. 2011. Colonization of citrus and citrus-related germplasm by Diaphorina citri (Hemiptera: Psyllidae). HortScience. 46(7):997-1005.

Interpretive Summary: Huanglongbing is a serious and devastating disease of citrus caused by a bacterium vectored by the Asian citrus psyllid. The disease has the potential to greatly limit the production of citrus in Florida and other citrus growing regions worldwide. Current control of the psyllid and huanglongbing is inadequate, but the identification and incorporation of plant traits that confer resistance in citrus to the psyllid is a potential psyllid/disease management strategy. In this study, citrus germplasm was assessed in a field study for resistance to natural South Florida populations of the psyllid. The majority of genotypes surveyed hosted all three life stages of the psyllid, however there were significant differences among genotypes in infestation levels of eggs, nymphs and adults. Although not completely avoided, very low levels of the psyllid were found on two surveyed genotypes of Poncirus trifoliata, Simmon’s trifoliate and Little-Leaf. Poncirus trifoliata readily forms hybrids with other citrus germplasm, is commonly incorporated into rootstock varieties, and has been used in breeding advance scion material. The identification of partial resistance in P. trifoliata to the psyllid may prove useful in future citrus breeding efforts aimed at reducing the incidence and spread of huanglongbing.

Technical Abstract: Huanglongbing (HLB) is a serious and devastating disease of citrus caused by Candidatus Liberibacter spp. and vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). The disease has the potential to greatly limit the production of citrus in Florida and other citrus growing regions worldwide. Current control of D. citri and HLB is inadequate, but the identification and incorporation of D. citri resistance traits from uncultivated Citrus spp. and Citrus relatives is seen as a potential disease management strategy. In this study, 87 Rutaceae genotypes, primarily in the orange subfamily Aurantioideae, were assessed in the field for resistance to natural South Florida populations of D. citri. The majority of genotypes surveyed hosted all three life stages of D. citri, however there were significant differences among the genotypes in the mean ranks for D. citri eggs (F = 3.13, df = 86, P < 0.0001), nymphs (F = 9.01, df = 86, P < 0.0001), and adults (F = 4.21, df = 86, P < 0.0001). The only sampled genotype that was completely avoided by all life stages of D. citri was Casimiroa edulis Llave et Lex, commonly known as white sapote, which was one of the few plants included in the study belonging to the Rutaceae subfamily Toddalioideae. Although not completely avoided, very low levels of D. citri were found on two surveyed genotypes of Poncirus trifoliata (L.) Raf, Simmon’s trifoliate and Little-Leaf. Poncirus trifoliata, the trifoliate orange, readily forms hybrids with Citrus spp., is commonly incorporated into rootstock varieties, and has been used in breeding advance scion material. The identification of partial resistance in P. trifoliata to D. citri may prove useful in future citrus breeding efforts aimed at reducing the incidence and spread of HLB.