The combination of Trichoderma virens Gl006 and B. velezensis Bs006 as a consortium has high potential to control Fusarium wilt (FW) of cape gooseberry (Physalis peruviana) caused by Fusarium oxysporum f. sp. physali (Foph). However, the interactions between these two microorganisms that influence the biocontrol activity as a consortium have not been studied. Here, we studied the interactions between Gl006 and Bs006 that keep their compatibility under in vitro and greenhouse conditions. Antagonism tests between Gl006 and Bs006 inoculated both individually and in consortium against Foph strain Map5 was carried out on several solid media. The effect of supernatant of each selected microorganism on growth, conidia germination, biofilm formation and antagonistic activity on its partner was also studied. Biocontrol activity by different combinations of cells and supernatants from both microorganisms against Fusarium wilt was evaluated under greenhouse conditions. In vitro antagonism of the consortium against Foph showed a differential response among culture media and showed compatibility among BCA under nutritional conditions close to those of the rhizosphere. The supernatant of Bs006 did not affect the antagonistic activity of Gl006 and vice versa. However, the supernatant of Bs006 promoted the biocontrol activity of Gl006 in a synergistic way under greenhouse, reducing the disease severity by 71%. These results prove the compatibility between T. virens Gl006 and B. velezensis Bs006 as a potential tool to control Fusarium wilt of cape gooseberry.Fusarium oxysporum is the causal agent of Fusarium wilt disease in several species of cultivated plants worldwide. This phytopathogen is in the fifth place within the top ten of the most important plant pathogens due to its effects in crops of economic importance causing severe losses 1 . Fusarium wilt is the main limitation of cape gooseberry (Physalis peruviana) crop in Colombia 2 . Wilt symptoms in field include wilting of top leaves, stunting of plants, lateral yellowing of branches and leaves, some plants present both dry and alive branches. Plants finally become yellow and die, resulting in plant losses and reduced fruit yield. This phytosanitary problem has also caused the migration of cropped areas within the country, but the problem persists in old and new cropped areas 2 . Currently, there are no registered phytosanitary products for the control of this disease in cape gooseberry.In this context, biological control has emerged as an environmentally sustainable alternative. However, classical biological control in which just one biological control agent (BCA) is used has shown high variability among tests. Considering that biocontrol agents are living organisms and they may not be active in all agroecosystems 3 , many of the recent studies have focused on using combinations of BCA to increase the efficacy against phytopathogens. Those combinations are known as consortia. A consortium is a microbial association of two or more microorganisms, which could be archaea, fu...

Background and aim Fusarium wilt (FW) is the major constraint on cape gooseberry (Physalis peruviana L.) production. Fungicides have been ineffective in disease control and alternative tools are not available. Bacillus velezensis (formerly Bacillus amyloliquefaciens) strain Bs006 has an antagonistic potential against Fusarium oxysporum f. sp. physali (Foph). However, results of

Banana, the main export fruit for Colombia, is threatened by Fusarium wilt (FWB), caused by Fusarium oxysporum f. sp. cubense (Foc), tropical race 4 (TR4). Pathogen containment through disinfecting tools, machinery, shoes, and any means that may carry contaminated soil particles with proper disinfectants is at the forefront of disease management. In this study, the biocide efficacy of 10 commercial quaternary ammonium compounds (QACs) products and one based on glutaraldehyde (GA) were evaluated on both reproductive structures (microconidia and macroconidia) and survival spores (chlamydospores) of Foc TR4 (strain 140038) isolated from La Guajira, Colombia. QACs were evaluated at 1200 ppm and two exposure times: <1 and 15 min in the absence or presence of soil. For GA disinfectant, four different concentrations (500, 800, 1200, and 2000 ppm) were evaluated at both contact times in the presence of soil. In the absence of soil, all QACs showed 100% biocidal efficiency against microconidia, macroconidia, and chlamydospores at both <1 and 15 min. The presence of soil decreased the efficacy of disinfectants, but some of them, such as QAC3_1st, QAC7_4th, and QAC5_4th, showed 98%, 98%, and 100% efficacy against Foc TR4 chlamydospores, respectively, after <1 min of contact time. For instance, the GA-based disinfectant was able to eliminate all Foc TR4 propagules after 15 min for all concentrations tested.

Biological control (BCAs) such as Trichoderma spp. minimize fungicides inputs in agriculture, and increase both the plant nutrition and the efficacy against fungal diseases. Novel bioproducts in crop management are called to guarantee sustainable antagonism activity of BCAs and increase the acceptance of the farmers. The encapsulation in polymeric matrices play a prominent role for providing an effective carrier/protector and long-lasting bioproduct. This research aimed to compare two hydrogel capsules prototypes based on alginate (P1) and amidated pectin (P2), containing Trichoderma koningiopsis Th003 conidia. Capsules were prepared by the ionic gelation method and calcium gluconate as crosslinker was used. The capsules were characterized by various properties such as conidia releasing at different pH values, drying conidia survival, storage stability, and biocontrol activity against sheath blight (R. solani) in rice. P2 prototype provided higher survival to Th003 up to 98% in fluid bed drying, faster conidia release at pH 5.8, storage stability > 6 months at 18°C, and a disease reduction up to 67%. Amidated pectin provides advantages on drying survival and conidia release at pH 5.8. Both biopolymers facilitate the antagonistic activity against R. solani, and therefore can be incorporated in hydrogel capsules for novel bioinoculants development. This research highlights the knowledge regarding the influence of biopolymer in hydrogel capsules on survival and shelf-life of Trichoderma spp conidia.

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