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Plants respond to environmental cues via adaptive cell reprogramming that can affect whole plant and ecosystem functionality. Microbiota constitutes part of the inner and outer environment of the plant. This Umwelt underlies steady dynamics, due to complex local and global biotic and abiotic changes. Hence, adaptive plant holobiont responses are crucial for continuous metabolic adjustment at the systems level. Plants require oxygen-dependent respiration for energy-dependent adaptive morphology, such as germination, root and shoot growth, and formation of adventitious, clonal, and reproductive organs, fruits, and seeds. Fermentative paths can help in acclimation and, to our view, the role of alternative oxidase (AOX) in coordinating complex metabolic and physiological adjustments is underestimated. Cellular levels of sucrose are an important sensor of environmental stress. We explored the role of exogenous sucrose and its interplay with AOX during early seed germination. We found that sucrose-dependent initiation of fermentation during the first 12 h after imbibition (HAI) was beneficial to germination. However, parallel upregulated AOX expression was essential to control negative effects by prolonged sucrose treatment. Early downregulated AOX activity until 12 HAI improved germination efficiency in the absence of sucrose but suppressed early germination in its presence. The results also suggest that seeds inoculated with arbuscular mycorrhizal fungi (AMF) can buffer sucrose stress during germination to restore normal respiration more efficiently. Following this approach, we propose a simple method to identify organic seeds and low-cost on-farm perspectives for early identifying disease tolerance, predicting plant holobiont behavior, and improving germination. Furthermore, the research strengthens the view that AOX can serve as a powerful functional marker source for seed hologenomes.

Somatic embryogenesis (SE) is the most striking and prominent example of plant plasticity upon severe stress. Inducing immature carrot seeds perform SE as substitute to germination by auxin treatment can be seen as switch between stress levels associated to morphophysiological plasticity. This experimental system is highly powerful to explore stress response factors that mediate the metabolic switch between cell and tissue identities. Developmental plasticity per se is an emerging trait for in vitro systems and crop improvement. It is supposed to underlie multi-stress tolerance. High plasticity can protect plants throughout life cycles against variable abiotic and biotic conditions. We provide proof of concepts for the existing hypothesis that alternative oxidase (AOX) can be relevant for developmental plasticity and be associated to yield stability. Our perspective on AOX as relevant coordinator of cell reprogramming is supported by real-time polymerase chain reaction (PCR) analyses and gross metabolism data from calorespirometry complemented by SHAM-inhibitor studies on primed, elevated partial pressure of oxygen (EPPO)–stressed, and endophyte-treated seeds. In silico studies on public experimental data from diverse species strengthen generality of our insights. Finally, we highlight ready-to-use concepts for plant selection and optimizing in vivo and in vitro propagation that do not require further details on molecular physiology and metabolism. This is demonstrated by applying our research & technology concepts to pea genotypes with differential yield performance in multilocation fields and chickpea types known for differential robustness in the field. By using these concepts and tools appropriately, also other marker candidates than AOX and complex genomics data can be efficiently validated for prebreeding and seed vigor prediction

Este artículo pretende i) revisar el estado del arte en el conocimiento de los problemas fitosanitarios reportados en las fases inicialesdel cultivo del cacao en el Ecuador, y ii) describir la presencia de tales problemas en viveros de Milagro. Las fuentes de informaciónfueron mixtas, y estas variaron según la escala geográfica. La información a nivel de país provino de libros o artículos; en cambio,para describir particularidades locales se utilizaron datos primarios de identificación de hongos e información facilitada por productoreslocales entrevistados. Al mismo tiempo, se usaron datos secundarios provenientes de tesis de pregrado, informes técnicosinstitucionales y artículos de prensa. La información secundaria, de poca visibilidad pero disponible en repositorios digitales, contieneinformación puntual válida para el conocimiento local. Los daños causados por hongos y por artrópodos (plagas sensu latu)se agruparon por síntoma y agente causal. De igual forma, se incluyen daños de origen abiótico. El manejo de los daños insectilesfue considerado de poca importancia por los viveristas, a diferencia de los causados por hongos y cromistas que constituyen eldesafío fundamental.ABSTRACTThis article aims i) to review the state of the art in the knowledge of phytosanitary problems reported in the initial stages of cacaocultivation in Ecuador, and ii) to describe the presence of such problems in Milagro vivariums. The sources of information were mixed,and these varied according to geographic scale. Information at the country level came from books or articles; in contrast, primary datato identify fungi and information provided by local farmers interviewed to describe local particularities, were used. At the same time,secondary data from undergraduate theses, institutional technical reports and press articles were used. Secondary information, withlow visibility but available in digital repositories, contains valuable information for local knowledge. The damages caused by fu

This article aims i) to review the state of the art in the knowledge of phytosanitary problems reported in the initial stages of cacaocultivation in Ecuador, and ii) to describe the presence of such problems in Milagro vivariums. The sources of information were mixed,and these varied according to geographic scale. Information at the country level came from books or articles; in contrast, primary datato identify fungi and information provided by local farmers interviewed to describe local particularities, were used. At the same time,secondary data from undergraduate theses, institutional technical reports and press articles were used. Secondary information, withlow visibility but available in digital repositories, contains valuable information for local knowledge. The damages caused by fungiand by arthropods (sensu latu pests) were grouped by symptom and causal agent. Symptoms of abiotic origin are also included. Themanagement of insect damage is considered of little importance by nurserymen, unlike those caused by fungi and chromists thatconstitute the fundamental challenge., Este artículo pretende i) revisar el estado del arte en el conocimiento de los problemas fitosanitarios reportados en las fases inicialesdel cultivo del cacao en el Ecuador, y ii) describir la presencia de tales problemas en viveros de Milagro. Las fuentes de informaciónfueron mixtas, y estas variaron según la escala geográfica. La información a nivel de país provino de libros o artículos; en cambio,para describir particularidades locales se utilizaron datos primarios de identificación de hongos e información facilitada por productoreslocales entrevistados. Al mismo tiempo, se usaron datos secundarios provenientes de tesis de pregrado, informes técnicosinstitucionales y artículos de prensa. La información secundaria, de poca visibilidad pero disponible en repositorios digitales, contieneinformación puntual válida para el conocimiento local. Los daños causados por hongos y por artrópodos (plagas sensu latu)se agruparon por síntoma y agente causal. De igual forma, se incluyen daños de origen abiótico. El manejo de los daños insectilesfue considerado de poca importancia por los viveristas, a diferencia de los causados por hongos y cromistas que constituyen eldesafío fundamental.