Effect of parental RNA interference of a transformer‐2 homologue on female reproduction and offspring sex determination in Asian citrus psyllid

Abstract

Abstract. Asian citrus psyllid Diaphorina citri Kuwayama is the vector of CandidatusLiberibacter asiaticus (CLas), the causal agent of citrus huanglongbing (HLB). A comprehensive understanding of molecular components that govern key physiological traits in D. citri would promote the development of novel genetic control strategies to fight this pest. In the present study, a transformer 2 homologue (Dctra-2) implicated in embryonic sex differentiation in dipteran insects is targeted to interfere with the offspring sex ratio of D. citri. The results of the present study show that Dctra-2 is constitutively expressed at all developmental stages and in both females and males during the adult stage. Quantitative reverse transcriptase-polymerase chain reaction analysis confirms the double-stranded RNA-mediated RNA interference (RNAi) of the Dctra-2. RNAi effects in D. citri female adults can be transferred in a trans-generational manner to their eggs and progeny, which are commonly referred as parental RNAi. RNAi females lay fewer eggs, with a mean of 12.44, and the hatching rate of laid eggs is reduced approximately by 29.86% compared with the control. However, parental RNAi of Dctra-2 do not produce male-biased progeny. The results suggest that Dctra-2 is an effective RNAi target for use in the management of D. citri. In addition, the parental RNAi would provide an effective tool for studying the function of early embryonic genes in D. citri.

Effect of silencing a boule homologue on the survival and reproduction of Asian citrus psyllid Diaphorina citri

“…Foliar application of actin‐dsRNA is reported to protect potato plants for almost 1 month and shows that the dsRNA is not easily washed off after drying (San Miguel & Scott, ). Notably, parental RNAi effects are observed in the D. citri offspring born from females exposed to dsRNA‐ Dctra‐2 (Yu & Killiny, ). This persistent RNAi effect in D. citri would further enhance the potential applications of RNAi strategy in agriculture.…”

“…RNAi efficacy in D. citri usually varies with the dsRNA delivery method and type of target genes, as well as the length and concentration of dsRNA fragment. Compared with the high levels of silencing reported in other research after the application of low amounts of dsRNA or even by the in planta system (Taning et al ., ; Andrade & Hunter, ; Yu et al ., ; Yu & Killiny, ), the present study shows that a robust RNAi is observed until feeding on 200 ng μL −1 of ds DcBol . Therefore, for each target gene of D. citri , an optimal concentration should be independently determined to achieve an efficient and optimal silencing effect.…”

“…Suitable target genes and efficient dsRNA delivery in insects are the two prerequisites of RNAi‐based insect management (Terenius et al ., ; Scott et al ., ; Yu et al ., ; Yu et al ., ). DsRNA delivery in D. citri has been conducted using artificial feeding (Galdeano et al ., ; Yu & Killiny, , b), soaking (Yu et al ., ), micro‐application of dsRNA (Killiny & Kishk, ; Kishk et al ., ), virus‐based RNAi (Hajeri et al ., ) and in planta systems (Hunter et al ., ; Taning et al ., ; Andrade & Hunter, ). The results of the present study demonstrate that virgin female adults feeding on an artificial diet with ds DcBol cause significant RNAi.…”

Characterization of NlHox3, an essential gene for embryonic development in Nilaparvata lugens

“…There were some specific studies into the role of parental RNAi in hemipteran insects. It was reported that parental RNAi of Dctra‐2 has a great influence on female fecundity and egg hatchability in Diaphorina citri (Yu & Killiny, ). It was also found that offspring wing morphs can be influenced by the maternal RNAi of the NlTra‐2 gene in a sex‐specific manner in N. lugens (Zhuo et al., ).…”

The secreted salivary proteome of Asian citrus psyllid Diaphorina citri

“…An aliquot of 150 μL of the diet was placed between two layers of stretched Parafilm membrane on the 9‐dram clear plastic vial (No. 55‐9; Thornton Plastics Co., Salt Lake City, Utah), with a hole (diameter 0.5 mm) on the side for air ventilation (Yu & Killiny, , b). Concentration, filtration and digestion procedures of soluble saliva were modified from that described previously by Carolan et al .…”