• First time B. bassiana and M. anisopliae introduced as endophytes in cassava roots. • Beauveria bassiana and M. anisopliae colonized cassava roots for up to 7 weeks. • Colonization of cassava roots by M. anisopliae remained relatively constant over time. • Colonization of cassava roots by B. bassiana declined over time. • Colonization levels were higher in the proximal end than in the distal end of the cassava root.

• Beauveria bassiana and M. anisopliae applied as seed treatment in common beans. • Both fungal entomopathogens become endophytic, with low colonization levels (<30%). • There was high variability in endophytic colonization. • Endophytism influenced by status of soil substrate used (sterile or non-sterile).

Studies involving fungal endophytes very often rely on surface-sterilisation of plant samples to enable endophyte isolations. However, surface-sterilisation can be very time-consuming, potentially limiting the number of samples processed. To overcome this limitation, a novel method was developed to bulk surface-sterilise multiple plant tissue samples simultaneously and separately. The method relies on 24 perforated Falcon™ tubes, each containing a sample, sequentially transferred through a series of containers holding the sterilants. The samples that can be surface-sterilised using this method include roots, stems and leaves or entire seedlings. This method increased our throughput by a factor of 24 relative to conventional surface-sterilisation methods.

Cassava Mosaic Disease (CMD) caused by Sri Lankan cassava mosaic virus (SLCMV), has rapidly spread in Southeast Asia (SEA) since 2016. Recently it has been documented in Lao PDR. Previous reports have identified whitefly species of B. tabaci as potential vectors of CMD in SEA, but their occurrence and distribution in cassava fields is not well known. We conducted a countrywide survey in Lao PDR for adult whiteflies in cassava fields, and determined the abundance and genetic diversity of the B. tabaci species complex using mitochondrial cytochrome oxidase I (mtCOI) sequencing. In order to expedite the process, PCR amplifications were performed directly on whitefly adults without DNA extraction, and mtCOI sequences obtained using nanopore portable-sequencing technology. Low whitefly abundances and two cryptic species of the B. tabaci complex, Asia II 1 and Asia II 6, were identified. This is the first work on abundance and genetic identification of whiteflies associated with cassava in Lao PDR. This study indicates currently only a secondary role for Asia II in spreading CMD or as a pest. Routine monitoring and transmission studies on Asia II 6 should be carried out to establish its potential role as a vector of SLCMV in this region.