Gut Microbiota Cannot Compensate the Impact of (quasi) Aposymbiosis in Blattella germanica

Blattella germanica presents a very complex symbiotic system, involving the following two kinds of symbionts: the endosymbiont Blattabacterium and the gut microbiota. Although the role of the endosymbiont has been fully elucidated, the function of the gut microbiota remains unclear. The study of the gut microbiota will benefit from the availability of insects deprived of Blattabacterium. Our goal is to determine the effect of the removal (or, at least, the reduction) of the endosymbiont population on the cockroach’s fitness, in a normal gut microbiota community. For this purpose, we treated our cockroach population, over several generations, with rifampicin, an antibiotic that only affects the endosymbiont during its extracellular phase, and decreases its amount in the following generation. As rifampicin also affects gut bacteria that are sensitive to this antibiotic, the treatment was performed during the first 12 days of the adult stage, which is the period when the endosymbiont infects the oocytes and lacks bacteriocyte protection. We found that after this antibiotic treatment, the endosymbiont population remained extremely reduced and only the microbiota was able to recover, although it could not compensate for the endosymbiont role, and the host’s fitness was drastically affected. This accomplished reduction, however, is not homogenous and requires further study to develop stable quasi-aposymbiotic cockroaches.

Research on the Knowledge-Sharing Incentive of the Cross-Boundary Alliance Symbiotic System

The rise of the cross-boundary alliance as a new organizational model profoundly affects innovation development. The incentive mode of knowledge-sharing among cross-boundary alliance members from the perspective of symbiosis is the key to improving the efficiency of knowledge-sharing and promoting the alliance’s sustainable development. Due to the interdisciplinary nature of knowledge and information asymmetry among alliance members, knowledge-sharing is prone to opportunistic behavior, which greatly impacts cross- boundary innovation cooperation. The symbiotic system of the cross-boundary alliance is constructed based on the analysis of symbiosis among alliance members to solve these problems. In this research study, the principal–agent theory is used to describe the expected benefits and the related constraints of knowledge-sharing partners. Moreover, an incentive model of knowledge-sharing in the cross-boundary alliance is established. By solving the model, the agent’s sharing intention and the principal’s reward incentive coefficient are obtained, which provide a theoretical basis for the formulation of the optimal incentive scheme of knowledge-sharing in the alliance. The results show that the knowledge potential difference, knowledge transmission efficiency, knowledge transformation, innovation effort, and the symbiotic environment will directly affect the knowledge transfer level of the alliance. In this research study, a theoretical research framework of the cross-boundary alliance symbiotic system linked by knowledge-sharing is constructed. The incentive model of knowledge-sharing is established especially on the basis of fully considering the internal and external factors of knowledge-sharing. This research study has provided some innovation in the theoretical system and method improvement, and has guaranteed the efficient integration, utilization, and innovation of knowledge resources in the cross-boundary alliance.

FabLab Barcelona—Co-design With Food Surplus: Better Redistributing, Upcycling and Composting

The chapter analyses a co-designed project in the food value chain. Looking at how to identify and stimulate new synergies among the local community in order to co-develop educational, logistic and environmental supports for better redistributing, upcycling and composting food locally, it critically presents the case of a Symbiotic System for food surplus and bio waste valorisation at a neighbourhood scale.

Microscopic studies of the phytoplasma infection effect on the symbiotic system Medicago sativa – Rhizobium meliloti in simulated conditions

Aim. Aim of the study was to microscopically investigate the interaction of Acholeplasma laidlawii var. granulum 118 with the target plant Medicago sativa, as well as to determine the role of Rhizobium meliloti strains with natural and defective polysaccharides in the plant’s resistance occurrence. Methods. Cultivation of plants and their inoculation with bacteria was performed under conditions of microvegetation experiment. The study of the ultrastructure of alfalfa roots and nodules was carried out with both light and electron microscopy. Results. The rhizobial mutant strain, defective in the synthesis of lipopolysaccharides, more often formed atypical nodules on M. sativa, which aged faster. In the variant with double inoculation of alfalfa with rhizobia together with acholeplasma changes in the morphology of the lateral roots of plants, as well as deformation of the nodules were observed. Conclusions. Results of this study indicate not only the ability of phytoplasmas to penetrate the root system and migrate to plant aboveground organs, but also demonstrate the possibility of their presence in the nodules formed by rhizobia. Keywords: Mollicutes, acholeplasma, rhizobia, mutant, lipopolysaccharides.

Chemical Gradients of Plant Substrates in an Atta texana Fungus Garden

The study of complex ecosystems requires an understanding of the chemical processes involving molecules from several sources. Some of the molecules present in fungus-growing ants’ symbiotic system originate from plants.