Endophytic bacteria of the Bacillus subtilis species complex are known for plant growth promotion and antifungal activity, although strain-specific traits remain poorly understood. This study characterized the Bacillus siamensis strain BACIII, isolated from asymptomatic soybean roots in a charcoal rot-affected area, using whole-genome analysis and phenotypic assays. Genome sequencing identified BACIII as Bacillus siamensis and revealed a metabolically versatile genome containing twelve biosynthetic gene clusters linked to antimicrobial compounds such as difficidin, fengycin, and surfactin. Additionally, genomic islands associated with mobile elements, regulation, and stress response suggest adaptive potential. Inoculation with the BACIII strain significantly accelerated germination and increased early growth, biomass accumulation, and chlorophyll content in soybean and sunn hemp (p < 0.05), whereas no significant effects were observed in cotton or sunflower, indicating host-dependent responses. In vitro assays demonstrated consistent inhibition of several phytopathogenic fungi, including Sclerotinia sclerotiorum, Fusarium spp., and Macrophomina phaseolina, with variable intensity. Overall, BACIII combines host-specific plant growth promotion with broad antifungal activity, supporting its potential for biological control in sustainable agriculture.

Interactions between insects and plants shape ecological and evolutionary dynamics, yet floral herbivory remains underdocumented for many taxa. Butterflies of the genus Battus have a specialized association with Aristolochia , with larval feeding historically reported only on vegetative tissues. Here, we present the first confirmed record of floral herbivory by larvae of Battus polydamas on Aristolochia gigantea . Observations were conducted on a single cultivated plant in the Evolutionary Garden of the University of Brasília. We quantified floral damage and documented larval behavior through photographs and videos. Of the 42 floral structures examined, 46.43% of open flowers and 35.71% of floral buds exhibited signs of herbivory, including laminar tissue removal, margin erosion, perforations, and partial destruction of the floral tube. Larvae of multiple instars were found feeding on both external and internal floral regions. These observations expand current knowledge of the feeding behavior of B. polydamas by documenting the use of floral tissues of A. gigantea. They also suggest potential ecological consequences of florivory for A. gigantea , emphasizing the need for broader investigations into the conditions and frequency of this interaction.