RESUMEN
Identifying the effectiveness of agricultural interventions is a challenge faced by many international aid initiatives. This article reports on our efforts to document the success of agricultural aid interventions. The study is focused on evaluating cacao projects in Colombia, specifically on assessing the success of the rural Productive Partnerships Project (PAAP). The two approaches used to assess the project's success included the degree of accomplishment of four of the PAAP project's objectives and a measurement of the project performance at the local level, for which an existing performance index was utilized. Quantitative data were obtained from the project's evaluation platform developed by the PAAP project coordinators. Based on our first evaluation approach, we found that the four project objectives evaluated were not fully accomplished. While our results using the performance index provide baseline data for upcoming work assessing cacao projects' performance, the absence of precedent information constrained its interpretation. Finally, the paper offers feasible, affordable, and practical recommendations that could benefit future program planning and evaluation of international aid interventions, particularly on cacao projects worldwide.
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Cacao , Humanos , Colombia , Evaluación de Programas y Proyectos de Salud , Desarrollo de ProgramaRESUMEN
BACKGROUND: Theobroma cacao is a major source of flavonoids such as catechins and their monomers proanthocyanidins (PAs), widely studied for their potential benefits in cardiovascular diseases. Light has been shown to promote plant secondary metabolite production in vitro. In this study, cacao cells cultured in 7.5 L stirred tank photobioreactors (STPs) were exposed to a change of white to blue LED lights for 28 days (d). RESULTS: Transcriptomic analyses were performed in three time points comparing changing expression patterns, after cell exposure to white light (d0-VS-d14), after a shift from white to blue light (d14-VS-d15), and after an extended period of blue light for the following 15 days (d15-VS-d28). Under white light, there was enrichment in metabolic pathways associated with cell growth (carbon, glycolysis, and amino acid biosynthesis) accompanied by a significant increase in the PAs content. In the shift to blue light, further increase in PAs content was observed concomitantly with the significant expression of TWO-COMPONENT RESPONSE REGULATOR genes involved in the early stress responses via circadian clock and hormone pathways. Under blue light exposure, we observed a depletion of PAs content associated with ROS-mediated stress pathways. CONCLUSIONS: Light effects on large-scale cell cultures in photobioreactors are complex and pleiotropic; however, we have been able to identify key regulatory players upstream cacao flavonoid biosynthesis in STPs, including TWO-COMPONENT SYSTEM and ROS-signaling genes. The crosstalk between flavonoid biosynthesis and regulatory networks led to understand the dynamics of flavonoid production and degradation in response to light-driven ROS signals. This can be used to optimize the time, and the yield of in vitro targeted metabolites in large-scale culture systems.
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Cacao , Cacao/genética , Flavonoides , Regulación de la Expresión Génica de las Plantas , Fotobiorreactores , TranscriptomaRESUMEN
Catechins, including catechin (C) and epicatechin (E), are the main type of flavonoids in cacao seeds. They play important roles in plant defense and have been associated with human health benefits. Although flavonoid biosynthesis has been extensively studied using in vitro and in vivo models, the regulatory mechanisms controlling their accumulation under light/dark conditions remain poorly understood. To identify differences in flavonoid biosynthesis (particularly catechins) under different light treatments, we used cacao cell suspensions exposed to white-blue light and darkness during 14 days. RNA-Seq was applied to evaluate differential gene expression. Our results indicate that light can effectively regulate flavonoid profiles, inducing a faster accumulation of phenolic compounds and shifting E/C ratios, in particular as a response to switching from white to blue light. The results demonstrated that HY5, MYB12, ANR and LAR were differentially regulated under light/dark conditions and could be targeted by overexpression aiming to improve catechin synthesis in cell cultures. In conclusion, our RNA-Seq analysis of cacao cells cultured under different light conditions provides a platform to dissect key aspects into the genetic regulatory network of flavonoids. These light-responsive candidate genes can be used further to modulate the flavonoid production in in vitro systems with value-added characteristics.
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Cacao/genética , Catequina/biosíntesis , Flavonoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Semillas/genética , Factores de Transcripción/genética , Cacao/citología , Cacao/metabolismo , Cacao/efectos de la radiación , Catequina/genética , Flavonoides/genética , Redes Reguladoras de Genes , Luz , Fotoperiodo , Células Vegetales/metabolismo , Células Vegetales/efectos de la radiación , Proteínas de Plantas/clasificación , Proteínas de Plantas/metabolismo , Semillas/citología , Semillas/metabolismo , Semillas/efectos de la radiación , Análisis de Secuencia de ARN , Factores de Transcripción/clasificación , Factores de Transcripción/metabolismo , TranscriptomaRESUMEN
Moniliophthora Pod Rot (MPR) caused by the fungus Moniliophthora roreri (Cif.) Evans et al., is one of the main limiting factors of cocoa production in Latin America. Currently insufficient information on the biology and epidemiology of the pathogen limits the development of efficient management options to control MPR. This research aims to elucidate MPR development through the following daily microclimatic variables: minimum and maximum temperatures, wetness frequency, average temperature and relative humidity in the highly susceptible cacao clone Pound-7 (incidence = 86% 2008-2013 average). A total of 55 cohorts totaling 2,268 pods of 3-10 cm length, one to two months of age, were tagged weekly. Pods were assessed throughout their lifetime, every one or two weeks, and classified in 3 different categories: healthy, diseased with no sporulation, diseased with sporulating lesions. As a first step, we used Generalized Linear Mixed Models (GLMM) to determine with no a priori the period (when and for how long) each climatic variable was better related with the appearance of symptoms and sporulation. Then the significance of the candidate variables was tested in a complete GLMM. Daily average wetness frequency from day 14 to day 1, before tagging, and daily average maximum temperature from day 4 to day 21, after tagging, were the most explanatory variables of the symptoms appearance. The former was positively linked with the symptoms appearance when the latter exhibited a maximum at 30°C. The most important variables influencing sporulation were daily average minimum temperature from day 35 to day 58 and daily average maximum temperature from day 37 to day 48, both after tagging. Minimum temperature was negatively linked with the sporulation while maximum temperature was positively linked. Results indicated that the fungal microclimatic requirements vary from the early to the late cycle stages, possibly due to the pathogen's long latent period. This information is valuable for development of new conceptual models for MPR and improvement of control methods.