Tomato Yellow Leaf Curl Virus Infection Alters Bemisia tabaci MED (Hemiptera: Aleyrodidae) Vulnerability to Flupyradifurone.

Baiming Liu,Xiaoguo Jiao,Youjun Zhang,Evan L Preisser,Joseph Munyaneza

doi:10.1093/jee/toaa118

Abstract

The whitefly, Bemisia tabaci Gennadius, is a major phloem-feeding pest of agricultural crops that is also an important vector of many plant diseases. The B. tabaci Mediterranean ('MED') biotype is a particularly effective vector of Tomato yellow leaf curl virus (TYLCV), a devastating plant pathogen. Although insecticides play an important role in the control of MED and TYLCV, little is known about how TYLCV infection affects MED susceptibility to insecticides. We conducted research addressing how MED susceptibility to flupyradifurone, the first commercially available systemic control agent derived from the butenolide class of insecticides, was affected by TYLCV infection. We first conducted bioassays determining the LC15 and LC50 for control and viruliferous MED feeding on either water- or insecticide-treated plants. We next measured several demographic parameters of control and viruliferous MED exposed to either insecticide- or water-treated plants. TYLCV infection increased MED tolerance of flupyradifurone: the LC15 and LC50 of viruliferous MED were double that of uninfected MED. Viral infection also altered MED demographic responses to flupyradifurone, but in an inconsistent manner. Although the ability of TYLCV and other persistently transmitted viruses to benefit Bemisia via manipulation of host plant defense is well known, this appears to be the first example of virally mediated changes in vector susceptibility to an insecticide.

Highlights

The whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a major phloem-feeding pest of both field and greenhouse crops worldwide (Stansly and Naranjo 2010)
Viruliferous MED were more tolerant of Sivanto than uninfected MED (Table 1)
Exposure to Sivanto marginally increased adult female longevity (Fig. 1A), increased first-week fecundity (Fig. 1B) and decreased egg-adult development time (Fig. 1C) in both MED groups (Table 2)

Summary

Introduction

The whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a major phloem-feeding pest of both field and greenhouse crops worldwide (Stansly and Naranjo 2010). Poses a particular threat to agriculture due to its invasiveness. Bemisia feeding can itself reduce plant growth, its primary threat to agriculture occurs via its ability to transmit a wide variety of plant viruses. MED is effective at transmitting such viruses, and its invasion is often associated with plant disease outbreaks (Ning et al 2015). TYLCV relies on B. tabaci as a vector to spread among plants (Fereres and Moreno 2009). Bemisia- plant-TYLCV interactions have been the subject of intense interest and researchers have confirmed the mutualistic relationship between B. tabaci and the virus.

Methods

Results

Conclusion