Complex multiple introductions drive fall armyworm invasions into Asia and Australia.

The fall armyworm (FAW) Spodoptera frugiperda is thought to have undergone a rapid 'west-to-east' spread since 2016 when it was first identified in western Africa. Between 2018 and 2020, it was recorded from South Asia (SA), Southeast Asia (SEA), East Asia (EA), and Pacific/Australia (PA). Population genomic analyses enabled the understanding of pathways, population sources, and gene flow in this notorious agricultural pest species.

Within-Season Changes in Land-Use Impact Pest Abundance in Smallholder African Cassava Production Systems.

Cassava ( Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly . In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected population dynamics and its parasitoids.

Improving climate suitability for Bemisia tabaci in East Africa is correlated with increased prevalence of whiteflies and cassava diseases.

Projected climate changes are thought to promote emerging infectious diseases, though to date, evidence linking climate changes and such diseases in plants has not been available. Cassava is perhaps the most important crop in Africa for smallholder farmers. Since the late 1990's there have been reports from East and Central Africa of pandemics of begomoviruses in cassava linked to high abundances of whitefly species within the Bemisia tabaci complex.

Evaluation of cultural control and resistance-breeding strategies for suppression of whitefly infestation of cassava at the landscape scale: a simulation modeling approach.

Background: The whitefly Bemisia tabaci is an important vector of virus diseases, impacting cassava production in East Africa. To date, breeding efforts in this region have focused on disease resistance. Here we use a spatially-explicit simulation model to explore how breeding strategies for whitefly resistance will influence the population dynamics of whitefly in the context of regional variation in cassava crop management practices.

African cassava whitefly, Bemisia tabaci, cassava colonization preferences and control implications.

Cassava is a staple food for people across sub-Saharan Africa. Over the last 20 years, there has been an increased frequency of outbreaks and crop damage in this region caused by the cassava-adapted Bemisia tabaci putative species. Little is known about when and why B.

Spectral separability and mapping potential of cassava leaf damage symptoms caused by whiteflies (Bemisia tabaci).

Background: This study examines whether leaf spectra can be used to measure damage to cassava plants from whitefly (Bemisia tabaci), and the potential to translate measurements from leaf to landscape scale in eastern Africa. Symptoms of the cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) viruses, and sooty mould (SM) blackening of lower leaves from whiteflies feeding on the upper leaves, were measured at the leaf scale with a high-resolution spectroradiometer and a single photon avalanche diode (SPAD) meter, which retrieves relative chlorophyll concentration. Spectral measurements were compared to the five-level visual scores used to assess the severity of each of the three damaging agents in the field, and also to leaf chemistry data.

Deletion of a gene encoding an amino acid transporter in the midgut membrane causes resistance to a Bombyx parvo-like virus.

Bombyx mori densovirus type 2 (BmDNV-2), a parvo-like virus, replicates only in midgut columnar cells and causes fatal disease. The resistance expressed in some silkworm strains against the virus is determined by a single gene, nsd-2, which is characterized as nonsusceptibility irrespective of the viral dose. However, the responsible gene has been unknown.