CO2 Fertilizer Effect on Growth, Polyphenols, and Endophytes in Two Baccharis Species

Abstract In a climate change context, the buildup of CO2 will affect plant communities worldwide. This study evaluated the effects of CO2 enrichment on the development and defense of two Cerrado native species Baccharis dracunculifolia and B. platypoda and their associated endophytic fungi richness. The study took place in Open-Top Chambers, two with ambient CO2 concentration (~400 ppm) and two in an enriched environment (~800 ppm). Baccharis platypoda developed 20% more leaves under enriched CO2 conditions, whereas B. dracunculifolia was 30% taller and showed 27% more leaves than those under ambient conditions. In both species, leaf polyphenol concentration did not differ between treatments. Nevertheless, polyphenol content had a positive correlation with plant height on both species' individuals grown under CO2 enriched conditions. Endophytic fungi richness and colonization rate on both plant species did not differ between ambient and enriched conditions. Our results show the positive effect of CO2 fertilizer in at least one of the measured growth parameters. An important new finding was a synergistic increase in growth and chemical defense in both studied species under enriched CO2 conditions, suggesting higher carbon assimilation and accumulation. This study suggests that the effects on primary productivity and secondary metabolites of Baccharis species will potentially reflect on the diversity and distribution of Cerrado plants and their associated animal communities.

Plasticidade fenotípica de Baccharis genistelloides subsp. crispa (Spreng. ) Joch. Müll. (2006) - Asteraceae - sob manejo orgânico / Phenotypic plasticity of Baccharis genistelloides subsp. crispa (Spreng. ) Joch. Müll. (2006) - Asteraceae - under organic management

O objetivo deste trabalho, relacionado a produção orgânica, utilizou preparados homeopáticos visando incremento na biomassa e no teor de flavonóides em plantas dióicas de carqueja. Os tratamentos foram: controle com água, controle com álcool 70%, Phosphorus 12CH, Sulphur 6CH, e a combinação destas homeopatias. Variações fenotípicas foram registradas a partir da análise de crescimento, realizada quinzenalmente durante 60 dias e dos caracteres morfológicos, tais como: como altura, número de ramificações, comprimento do ramo principal, diâmetro do caule e ala caulinar mediana. Na colheita foram medidos: a fitomassa fresca/seca e o volume de raiz. Posteriormente, foi quantificado o teor de flavonóides totais conforme as análises prescritas pela Farmacopéia Brasileira. O experimento foi avaliado em delineamento de blocos casualizados (2x5x2), sendo suas médias avaliadas pelo teste Tukey e o coeficiente de variação ambiental para estimar a plasticidade. Quanto ao estudo do crescimento da planta ao longo do tempo, verificou-se aumento linear simples para a maioria das variáveis nos dois sexos. Foram detectadas respostas plásticas na maioria dos caracteres avaliados. De acordo com os resultados, em ambos os sexos, 60 dias de cultivo são suficientes para obtenção de matéria prima com teor aceitável de flavonóides, bem como para verificação dos efeitos de patogenesia e similitude na aplicação de preparados homeopáticos Phosphorus 12CH, Sulphur 6CH e sua combinação Phosphorus 12CH + Sulphur 6CH. A fitomassa e o teor de flavonóides totais foram semelhantes entre plantas dióicas durante o período de estudo.

This study looked at organic production, in addition to the use of homeopathic preparations, in order to increase biomass and flavonoid content in dioecious plants of Baccharis genistelloides. The adopted treatments were: water control, control with 70% alcohol, Phosphorus 12CH, Sulphur 6CH and a combination of them. Phenotypic changes were recorded for the growth analysis, performed biweekly for 60 days, of the morphological features, such as height, number of branches, length of the main branch, diameter of the stem and median stem wing. At harvest, we measured the fresh/dry phytomass and root volume. Subsequently, we quantified the content of total flavonoids according to the analyses required by the Brazilian Pharmacopoeia. The experiment was evaluated in a randomized block design, and its averages were evaluated by the Tukey's test and environmental variation coefficient to estimate plasticity. As for the study of plant growth over time, there was a simple linear increase for most of the variables in both genders. We could detect phenotypic plasticity traits in most features analyzed. According to these results in both genders, 60 days after inoculation are sufficient to obtain raw material with acceptable level of flavonoids, as well as pathogenesis and similar effects in the application of homeopathic preparations of Phosphorus 12CH, Sulphur 6CH and their combination. Phytomass and content of total flavonoids were similar between the dioecious plants during the study period.