Agricultural systems in Amazonia depend on the management of mycorrhizal fungi.

A large number of useful tropical plant species are dependent on mycorrhizal fungi. Without the fungal symbionts they show growth depression and lower tolerance to biotic and abiotic stresses. In plant production systems, common management practices normally result in symbiosis deficits. In tropical regions where the system of shifting cultivation is practiced, the fallow period was thought to have a positive regulating effect on the mycorrhizal situation. It's showed that between three and eight years of fallow there is an increase of the inoculum potential in the soils but the effectivity of the fungal populations remains very low in comparison to the populations from natural sites. The need to manage the mycorrhizal fungi in situ in the field is discussed

Recultivation of abandoned monoculture areas in Amazonia.

The project concerns an experiment in recultivating a fallow rubber plantation of 19 ha by establishing mixed plantations of selected crops, mainly tree. In order to achieve sustainability, different crop combinations and different strategies for management of the spontaneous vegetation will be tested, and the crop systems will be stabilized by inoculation the plants with spores of mycorrhizal fungi. The experimental area was divided into five blocks with eighteen plots each to test four mixed cultivation systems, compared to four conventional monoculture systems. Fallow plots will be analyzed for reference. The scientific research is focused on the ecological role of mycorrhizal fungi in the field trial, analysis of the structural and functional traits of the structural and functional traits of the spontaneous vegetation due to management, and identification and control of plant diseases. In addition, economic and acceptance studies will be conducted to find out whether farmers are willing to apply the tested cultivation systems. In the 19 ha plantation, intend to test the three following ways of stabilizing crops using different variants and to analyze the crop systems on a scale that is close to practical conditions: 1. inoculation of the plants with spores of mycorrhizal fungi; 2. testing of different mixed cultivation systems; and experiment on management of the spontaneous vegetaion in the crop systems to improve the competitive conditions for the planted crops

Isolation, selection and production of vesicular-arbuscular mycorrhizal fungi (VAMF) and their application in mixed cropping systems.

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Isolation, selection and production of vesicular-arbuscular mycorrhizal fungi (VAMF) and their application in mixed cropping systems.

The introduction of VAMF into agricultural systems benefits the growth and the health of the crops, especially in abandoned areas with poor soils. As a pre-requisite for the application of the symbiots, the fungi must be isolate and selected with respect to their efficiency for the plants and their adaptability to the environmental conditions in the field. Different methods of isolation and the selection procedure are described. The mass production of the selected fungi can be carried out in the greenhouse or in the field. The inoculation of the plants with the VAMF is possible in the nurseries as well as in the field. Two methods of application - inoculation of the plants with a homogenous mixture of the inoculum in the substrate and with a concentrated inoculum layer respectively - are presented

Time-Fractional Optimal Control of Initial Value Problems on Time Scales

We investigate Optimal Control Problems (OCP) for fractional systems involving fractional-time derivatives on time scales. The fractional-time derivatives and integrals are considered, on time scales, in the Riemann--Liouville sense. By using the Banach fixed point theorem, sufficient conditions for existence and uniqueness of solution to initial value problems described by fractional order differential equations on time scales are known. Here we consider a fractional OCP with a performance index given as a delta-integral function of both state and control variables, with time evolving on an arbitrarily given time scale. Interpreting the Euler--Lagrange first order optimality condition with an adjoint problem, defined by means of right Riemann--Liouville fractional delta derivatives, we obtain an optimality system for the considered fractional OCP. For that, we first prove new fractional integration by parts formulas on time scales.Comment: This is a preprint of a paper accepted for publication as a book chapter with Springer International Publishing AG. Submitted 23/Jan/2019; revised 27-March-2019; accepted 12-April-2019. arXiv admin note: substantial text overlap with arXiv:1508.0075

Measurement of negatively charged pion spectra in inelastic p+p interactions at plabp_{lab} = 20, 31, 40, 80 and 158 GeV/c

We present experimental results on inclusive spectra and mean multiplicities of negatively charged pions produced in inelastic p+p interactions at incident projectile momenta of 20, 31, 40, 80 and 158 GeV/c ($\sqrt{s} =$ 6.3, 7.7, 8.8, 12.3 and 17.3 GeV, respectively). The measurements were performed using the large acceptance NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. Two-dimensional spectra are determined in terms of rapidity and transverse momentum. Their properties such as the width of rapidity distributions and the inverse slope parameter of transverse mass spectra are extracted and their collision energy dependences are presented. The results on inelastic p+p interactions are compared with the corresponding data on central Pb+Pb collisions measured by the NA49 experiment at the CERN SPS. The results presented in this paper are part of the NA61/SHINE ion program devoted to the study of the properties of the onset of deconfinement and search for the critical point of strongly interacting matter. They are required for interpretation of results on nucleus-nucleus and proton-nucleus collisions.Comment: Numerical results available at: https://edms.cern.ch/document/1314605 Updates in v3: Updated version, as accepted for publicatio