Transmisión del Mal de Río Cuarto virus por ninfas de primer y tercer estadio de Delphacodes kuscheli

Abstract

Resumen -Se comparó la capacidad de ninfas de primer y tercer estadío de Delphacodes kuscheli Fennah (Hemiptera: Delphacidae) para adquirir y posteriormente transmitir el Mal de Río Cuarto virus (MRCV), bajo condiciones controladas. Ninfas I y III avirulíferas se alimentaron separadamente de plantas de trigo infectadas durante 48 horas, para luego ser colocadas en subgrupos de tres individuos sobre plantas de trigo sanas. Se realizaron transmisiones seriales utilizando períodos de inoculación de 24 horas. Ambos estadiíos lograron adquirir y transmitir el MRCV, pero se evidenció una mayor cantidad de subgrupos infectivos cuando la adquisición se efectuó como ninfas I, así como una disminución significativa en la duración del período de latencia del virus respecto de los insectos que adquirieron el MRCV durante el tercer estadio ninfal.Términos para indexación: Delphacidae, Reoviridae, transmisión experimental, período de latencia. Transmission of Mal de Río Cuarto virus by first and third-instar nymphs of Delphacodes kuscheliAbstract -The ability of first and third-instar Delphacodes kuscheli Fennah (Hemiptera: Delphacidae) nymphs to acquire and transmit Mal de Río Cuarto virus (MRCV), under controlled conditions, was investigated. First and third-instar nymphs were allowed acquisition feeding separately on infected wheat plants for 48 hours. The insects were then placed in groups of three for serial transmissions to healthy wheat plants, using inoculation periods of 24 hours. Both instars of D. kuscheli were demonstrated to acquire and subsequently transmit the virus. Nevertheless, transmission trials showed highest transmission efficiency and shortest latent period when MRCV was acquired by first-instar nymphs.

High Viral Load in the Planthopper Vector Delphacodes kuscheli (Hemiptera: Delphacidae) is Associated With Successful Transmission of Mal de Río Cuarto Virus

“…1). These results are in accordance to previously published work on MRCV experimental transmission by D. kuscheli (Arneodo et al 2005).…”

“…Under experimental conditions, Ϸ30Ð50% of D. kuscheli planthoppers that feed on a MRCV-infected plant can transmit the virus to wheat after a maximum latency period of 17 d (Arneodo et al 2002). Moreover, it has been demonstrated that when D. kuscheli acquires the virus as a Þrst-instar nymph, the transmission efÞciency is higher than when the acquisition occurs during the third instars (Arneodo et al 2005). However, little is known about the mechanisms underlying MRCV transmission and the causes of the low and variable transmission efÞciency achieved under experimental conditions.…”

Immunodetection and subcellular localization of Mal de Río Cuarto virus P9-1 protein in infected plant and insect host cells

“…Laboratory-reared first instar nymphs were used based on previous experiments [25]. After a 12-day latent period, the insects were recovered and individually tested for infectivity through experimental transmissions to select the viruliferous specimens [25,26].…”

Insights Into Insect Vector Transmission and Epidemiology of Plant-Infecting Fijiviruses

“…Generally, the virus is more efficiently acquired by nymphs than by adults. In two similar examples, FDV is transmitted by P. saccharicida only if the virus is acquired by first-instar nymphs, but not older instars or adults, and first-instar nymphs of D. kuscheli transmit MRCV with higher efficiency compared with older instar nymphs (Hutchinson and Francki, 1973;Arneodo et al, 2005).…”