W. Chan-Cupul, J. M. Palma-Garcia, E. Ruiz-S & aacute;nchez, and E. Cruz-Crespo. 2025. Assessment of the effects of inoculation with entomopathogenic fungi on the vegetative growth and yield of Capsicum chinense under water stress conditions. Int. J. Agric. and gastronomic value. The cultivation of C. chinense is increasingly challenged by global warming and droughts, which impact both plant health and market stability. Climate change affects agriculture by altering temperature and precipitation patterns, leading to soil moisture loss, drought, phenological damage, and increased pest and disease incidence. The use of bioinoculants, including entomopathogenic fungi (EFs), may be a strategy to mitigate drought in C. chinense production. The aim of this study was to assess the impact of Beauveria brongniartii and Purpureocillium lilacinum inoculation on the vegetative growth and yield of C. chinense var. Chichen Itza under two water stress conditions. Experiments were conducted in a gothic greenhouse, and C. chinense seedlings were transplanted into growth bags [coconut fiber (70%) and dust (30%)] with controlled irrigation at 75% and 100% levels. The EFs were applied weekly for the first month (50 mL at 1x107 conidia mL-1). Agronomic parameters, including plant height, stem diameter, chlorophyll index, leaf area, fruit quality, and yield, were measured. The results indicated that both B. brongniartii and P. lilacinum significantly increased plant height and stem diameter in the early stages of growth under water stress conditions. B. brongniartii notably increased plant growth and maintained fruit yield even under reduced irrigation. However, no significant differences were observed in the chlorophyll index or overall fruit yield among the treatments. The results of this study suggest that B. brongniartii and P. lilacinum can improve C. chinense resilience to water stress, suggesting potential applications in sustainable agriculture amidst climate change.

Rotylenchulus reniformis poses a significant threat to cotton crops in the Brazilian Cerrado, particularly when grown consecutively with soybeans. This nematode has not only become a concern for cotton but has also led to considerable damage in soybean crops, emphasizing the need for effective nematode control in both agricultural settings. The aim of this study was to combine genetic control with the application of biological nematicides, as seed treatment, to manage R. reniformis under greenhouse conditions. Two soybean cultivars, TMG 4182 and Fibra, resistant and susceptible, were used and the biological nematicides used included Purpureocillium lilacinum, Trichoderma harzianum + T. asperellum + Bacillus amyloliquefaciens, B. subtilis + B. licheniformis, and B. firmus. Inoculation with 800 R. reniformis occurred in the cotyledonary stage, with evaluations conducted at 72 and 76 days after inoculation for Experiments 1 and 2, respectively. Nematodes were extracted from the soil and roots, calculating the reproduction factor (RF). The combination of biological nematicides with resistant cultivars did not yield substantial benefits in controlling reniform nematodes in soybean but safeguarding resistant cultivars through the application of chemical or biological nematicides is important to mitigate inoculum pressure on resistance genes. In addition, biological nematicides evaluated in this study did not improve soybean plant development and we concluded that managing reniform nematodes in soybean necessitates the integration of diverse control measures to effectively address the challenges posed by this nematode's impact on crops.

Root-knot nematodes (RKNs) are distributed globally, including in agricultural fields contaminated by heavy metals (HM), and can cause serious crop damages. Having a method that could control RKNs in HMcontaminated soil while limit HM accumulation in crops could provide significant benefits to both farmers and consumers. In this study, we showed that the nematophagous fungus Purpureocillium lavendulum YMF1.683 exhibited a high nematocidal activity against the RKN Meloidogyne incognita and a high tolerance to CdCl2. Comparing to the P. lavendulum YMF1.838 which showed low tolerance to Cd2+, strain YMF1.683 effectively suppressed M. incognita infection and significantly reduced the Cd2+ uptake in tomato root and fruit in soils contaminated by 100 mg/kg Cd2+. Transcriptome analyses and validation of gene expression by RT-PCR revealed that the mechanisms contributed to high Cd-resistance in YMF1.683 mainly included activating autophagy pathway, increasing exosome secretion of Cd2+, and activating antioxidation systems. The exosomal secretory inhibitor GW4869 reduced the tolerance of YMF1.683 to Cd2+, which firstly demonstrated that fungal exosome was involved in HM tolerance. The up-regulation of glutathione synthesis pathway, increasing enzyme activities of both catalase and superoxide dismutase also played important roles in Cd2+ tolerance of YMF1.683. In Cd2+contaminated soil, YMF1.683 limited Cd2+-uptake in tomato by up-regulating the genes of ABCC family in favor of HM sequestration in plant, and down-regulating the genes of ZIP, HMA, NRAMP, YSL families associated with HM absorption, transport, and uptake in plant. Our results demonstrated that YMF1.683 could be a promising bio-agent in eco-friendly management of M. incognita in Cd2+ contaminated soils.