Dragon fruit cultivation is an emerging industry in Ecuador. In August of 2020, yellow dragon fruit plants (Hylocereus megalantus) showing brown hardened scabs on cladodes and fruits were observed ...

The occurrence of Schlumbergera virus X (SchVX) in commercial dragon fruit fields in three provinces of Ecuador has been identified in this study. The virus was found in symptomatic and asymptomatic cladodes of the two major species (Hylocereus undatus and H. megalanthus) cultivated in the country. Symptoms in H. undatus included irregular and ring-shaped chlorotic spots that coalesce into large chlorotic patches along the cladodes, whereas small chlorotic spot symptoms on the cladodes were observed in H. megalanthus. Phylogenetic inferences based on 27 partial nucleotide sequences of the RNA-dependent RNA polymerase (RdRp) and three whole genome comparisons showed that Ecuadorean isolates from H. undatus and H. megalanthus share a most recent ancestor with isolates from Spain and Portugal. In addition, an SchVX isolate with a distinct genomic lineage was found in symptomatic H. polyrhizus plants from a single location, suggesting two independent virus introductions into the country.

Hermetia illucens is an important species for waste management and the circular economy. The aim of this study was to analyze the effects of Trichoderma reesei C2A and Pleurotus sp. as pretreatments of brewer spent grain (BSG). BSG was inoculated with fungal solution or distilled water (control). After seven days, this was used for H. illucens larvae cultivation. At the end of bioconversion process, parameters of substrate reduction and H. illucens larval development were evaluated. Chemical properties of BSG, frass and larvae were also analyzed. With T. reesei C2A pretreatment, highest substrate reduction (46.3 ± 0.9%) was achieved, but larval growth rate was lower (1.0 ± 0.1 mg/d) than that of control (2.8 ± 0.2 mg/d). Larvae of Pleurotus sp. pretreatment had limited development, reflected in their negative growth rate (−0.6 ± 0.2 mg/d). In conclusion, cultivation of H. illucens larvae (six day old) on BSG pretreated with Pleurotus sp. is not recommended. On the other hand, T. reesei C2A pretreatment enhance BSG reduction, and its potential use for lignocellulosic waste management should be more explored.

The growing generation of organic solid waste from small-scale agriculture poses major environmental challenges in developing countries like Ecuador, where rural areas often lack waste management infrastructure. Residues from livestock rearing and traditional brewing such as poultry manure (PM), bovine manure (BM), and barley by-product (BB) are often discarded untreated. This study evaluated the bioconversion potential of Hermetia illucens (black soldier fly larvae (BSFL), using a local Ecuadorian strain reared on these substrates under natural conditions and three feeding rates (50, 100, and 150 mg·larva⁻¹·day⁻¹). Larval growth and process efficiency were analyzed on a dry-matter basis. Both substrate and feeding rate significantly influenced performance (p < 0.05). PM and BB produced the highest larval dry weights (37.4 and 35.9 mg, respectively) at 100 mg·larva⁻¹·day⁻¹, with development completed in 35 days. BM-fed larvae reached only 17.6 mg and required up to 91 days. Bioconversion peaked at 4.6% (PM100) and 4.2% (BB50), while all BM treatments showed very low efficiency (<0.8%). Waste reduction was highest in BB100 (52.9%) and PM100 (43.5%). These results demonstrate the potential of BSFL as a biological treatment option for rural organic waste streams; however, performance strongly depended on substrate quality and feeding rate, indicating that not all locally available residues are equally suitable for larval bioconversion.