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Bitter vetch (Vicia ervilia (L.) Willd.), a grain legume crop well adapted in marginal soils, has mainly been used for animal feed. Nowadays, bitter vetch seeds in feed formulations are replaced by other protein sources such as soybean meal. However, in the context of sustainable economic development, it may be beneficial to enhance the cultivation of bitter vetch landraces in marginal areas. Fifty-six bitter vetch accessions of different provenance were preliminarily characterised by microsatellite DNA analysis to discriminate landraces suitable for specific and restricted environments. Twenty-two landraces of two genetically different groups were then selected for further characterisation by agro-morphological analyses. Being late-flowering with a seed yield of up to 3–4 t ha–1 in experimental field conditions, with neither chemical nor water input, these plants will be valuable material for long-term study to develop new cultivars adapted for seed production under organic agricultural systems in Southern Europe. The seeds of these 22 landraces were also evaluated, with positive results, as partial replacement of soybean in rabbit diets.

We study the possibility to use Single Photon Avalanche Diodes (SPAD) as photodetectors for applications in space missions. SPADs are silicon devices operated above the junction breakdown voltage (with the typical overvoltage of 5V), for which a single photon interacting in the active region is sufficient to trigger a self-sustainable avalanche discharge. SPADs can thus be used for the detection of very low light levels with a fast time response around 50ps FWHM for single photon detection, without spectroscopic capabilities. Large area SPAD (500 µm in diameter) have been designed and fabricated at the CNR-IMM facility, with an intrinsic noise lower than 10kHz at -15°C, before irradiation. We performed bulk damage radiation tests with protons in order to evaluate their radiation hardness properties and their suitability for application in a Low Earth Orbit (LEO) space mission. With this aim SPAD devices have been irradiated up to 3×109 (28.5 MeV) p/cm2. The test performed show that large area SPAD are very sensitive to proton doses as low as 1×108 p/cm2 with a significant increase in dark counts rate as well as in the manifestation of the "random telegraph signal" effect. Lower protons doses in the range 1-5×107 p/cm2 result in a lower increase of DCR suggesting that applicability in low-inclination LEO, particularly useful for gamma-ray astrophysics, is still feasible.

We study the possibility to use Single Photon Avalanche Diodes (SPADs) optically coupled to scintillating fibers as a novel type of gamma-ray detector for space applications. SPADs are silicon devices operating under polarization conditions above the junction breakdown voltage (typical overvoltage of 5V), for which a single photon interacting in the active region is sufficient to trigger a self sustainable avalanche discharge. SPADs can thus be used for the detection of very low light levels with an absolute timing accuracy of about 30 ps for single photon detection, without spectroscopic capabilities. In this presentation we report the preliminary results on large area SPAD (actual results refers to SPADs having 200 ?m diameter, with the aim to grow up to 500 ?m SPADs) coupled to scintillating fibers as the basic module for a particle tracker for space application. Dark counts rate as low as few tens of kHz at room temperature, lowering down to few kHz at -10°C have been obtained for the 200 ?m devices, in accordance with the basic requirements for the proposed application. Similar instruments based on silicon photomultiplier (SiPM) readout have already been studied, but none based on SPAD has been realized up to now. Moreover, since very few information is available on SPADs for the use in a space environment, we performed bulk damage and total dose radiation tests with protons and gamma-rays in order to evaluate their radiation hardness properties and their suitability for application in a Low Earth Orbit (LEO) space mission. With this aim the SPAD devices have be irradiated using up to 20 krad total dose with gamma-rays and 5 krad with protons