No abstract

Orchids require symbiotic fungi and/or specific conditions to germinate. Asymbiotic techniques have been shown successful for orchid germination. In Chile, Chloraea include many endemic, and potentially ornamental, terrestrial orchid species. In this study, individuals of Chloraea crispa, C. gavilu and C. virescens were manually autopollinated. The resulting capsules were sterilized and seeds were aseptically obtained. We evaluated asymbiotic germination in: Agar Water (AW), Knudson C (KC), Banana Culture Media (CMB), Tomato Culture Media (CMT), Malmgren Modified (MM), Murashige and Skoog (MS), and MS modified (MS1/2). Seeds were incubated in the dark at 24±1 ºC for 2 weeks. Then they were put in 16/8 h light/dark cycles for 14 weeks. We registered germination and embryo development in the different culture media. After 8 weeks, all tested Chloraea species germinated in most culture media. After 16 weeks, embryos in MM showed an evident shoot. In AW only the pre-germination stage was achieved. In C. gavilu germination was over 90% in MM, CMT, and CMB. In KC, a lower germination was obtained in all tested species compared to the other culture media, except for AW. Asymbiotic germination of endemic Chilean orchids could be a viable strategy for their conservation and propagation as ornamental species.

Chloraea is a diverse orchid genus with many endemic Chilean species. Many of those species have conservation problems, and the status of their populations is unknown. Chloraea disoides Lindl. is a Critically Endangered species endemic to Chile with a narrow distribution, and many of its registered populations are located in highly disturbed sites. The restricted distribution, the increasing anthropic disturbances, and global change could lead to the rapid extinction of C. disoides. Our work aims to characterize actual populations (in Valparaíso and one in Angol), design an index to determine the conservation status of these populations, and study the potential impact that the reduction in precipitations could have on the distribution of this species, as predicted by climate change models. Using herbarium data and field collections, we registered the populations of C. disoides present in Chile and modeled the potential distribution of the species using computer models based on climatic variables. We also characterized two populations at the two ends of its distribution (Valparaíso in the north and Angol in the south). The predictive model resulted in a very narrow potential distribution for the species, superposing known populations. Some of the historical populations are now urbanized areas. Valparaíso (northern) populations presented a very low density of C. disoides individuals. Both studied populations were highly disturbed with evidence of cattle damage and human influence. Chloraea disoides is seriously threatened by anthropogenic disturbances, especially since its distribution is very narrow and the species is not well represented in protected areas. Conservation initiatives should include protection of some of the natural populations and ex situ reproduction/propagation using fungal isolates.

Ecuador is responsible for up to 70 % of the world's production of fine flavor cocoa.Although fungal diseases have reduced cocoa production, eco-friendly alternatives have been implemented to control the spread of phytopathogens. This study aimed to explore the potential of endophytic strains isolated from fine flavor Nacional cocoa trees to synthetize compounds with antimicrobial and surface active properties. It was determined that under in vitro conditions, seven strains (DS03, DS07, DS18, DS23, DS31, DS34 and DS50) exhibited antifungal activity that inhibited the mycelial growth of Moniliophthora roreri and Moniliophthora perniciosa. The strains were identified based on their morphological (pattern forming Bacilli) and genetic characteristics using the 16S SSU rRNA gene sequences. Furthermore, we determined that the endophytic strains contained genes that encoded the lipopeptides Fengycin (fenA, fenB, fenC, fenE), Iturin (ituB, ituC, ituD), and Bacyllomicin D (bamC, bamD). The production of biosurfactant compounds was determined by a reduction in surface tension in the mineral medium. Additionally, the biosurfactant crude extract (BCE) was tested for its inhibitory activity against M. perniciosa and M. roreri. The minimal inhibitory concentration (MIC) was determined to be 0.07 and 0.035 mg mL -1 , respectively, in both cases in a fungistatic action mode. The swelling granulation and fragmentation of both phytopathogens' hyphae were observed using the BCE treatment.These results suggested the biocontrol capacity of the endophytic strains, which under in vitro conditions, have the ability to synthesize antifungal and surface active compounds that might be used as an ecological alternative in cocoa plants to prevent infection by phytopathogens.

Almost all orchid species depend on association with fungal partners. These fungal species facilitate orchid seed germination and promote growth and possibly stress tolerance in adult plants, both in the field and laboratory conditions. Codonorchis lessonii is a terrestrial orchid, endemic to southern Chile and Argentina with a currently unknown conservation status. Previous studies have reported Rhizoctonia-like fungi associated with C. lessonii in Argentina, but their fungal partners in Chilean populations are unknown. This study aims to characterize and isolate the mycorrhizal fungi associated with adult individuals of C. lessonii from three different populations in Central-South Chile. Root sections showing pelotons were used for the isolation and identification of the fungal taxa. Radial fungal growth was measured for all mycelial isolates. The presence of binucleate cells placed all isolates within the families Ceratobasidiaceae and Tulasnellaceae and the identification was confirmed by molecular analysis. Fungal isolates belonging to Ceratobasidiaceae grew at a higher rate than those from Tulasnellaceae. Phylogenetic analyses showed that different fungal partners associate with this orchid, suggesting relatively low specificity. The isolation and identification of the fungal partners of C. lessonii could help understand its ecology and contribute in future restoration and propagation initiatives for the species.