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Plants are subjected to a wide range of stresses which reduces the productivity of agricultural crops. In the case of cereal cultivations, climate change impacts on their production mainly through abiotic and biotic stress due for example to heat and water stress but also to pathogens such as bacteria, fungi, nematodes and others. The area under cereal cultivation is increasing worldwide, but, due to these problems, the current rates of yield growth and overall production are not enough to satisfy future demand. For this motivation, there is the needs to monitor and to control the cultivations, also developing new technological solutions useful to better optimize the management strategies, increasing both the quality of products and the quantity of the annual cereal harvest. Infrared imaging is a well-known non-invasive and non-contact technique that represents an outstanding approach of analysis applied in many fields: engineering, medicine, veterinary, cultural heritage and others. In recent years it has been gaining great interest in agriculture as it is well suited to the emerging needs of the precision agriculture management strategies. In this work, we performed an in-field multispectral infrared monitoring of different cereal crops (durum wheat and common wheat) through the use of both LWIR and MWIR cameras. The monitoring carried out made it possible to identify, among the crops analyzed, those subject to higher stress levels and their response to the different spectral ranges used. The results obtained open to the possibility of identifying new figures of merit useful for an effective monitoring of cereal crops and measurable through remote instrumentation.

Soil erosion is one of the biggest environmental problems throughout European Union causing considerable soil losses. Vegetation cover provides an important soil protection against runoff and soil erosion. To this aim, unlike annual crops, perennial plants have the advantage of covering soil for a longer time and reducing soil erodibility thanks to SOM increase due to litter effect and to reduction of soil disturbance (no-tillage). Two experiments were carried out in marginal hilly areas (10% slope) of Southern Italy: i) long-term experiment in which it was evaluated the effect of two fertilization doses (N: 100 and 50 kg N ha−1 from urea) on Arundo donax L. biomass production as well as its effect on soil erosion; ii) three-year experiment to evaluate the soil cover capacity of the giant reed by analysing the plant leaf area index (LAI). Results of the two experiments showed a good soil protection of Arundo donax L. that reduced soil losses by 78% as compared to fallow and showed soil erosion reduction not different from permanent meadow thanks to the soil covering during the period with the highest rain erosivity and to the reduction in soil erodibility. The protective effect of Arundo donax L. from rain erosivity was also confirmed by LAI analysis that showed a good soil covering of giant reed in the above mentioned period, even during the initial yield increasing phase following crop transplant. According to biomass yield, from the fifteen year of cultivation in a low fertile inland hilly area of Southern Italy, giant reed was characterized by a yield-decreasing phase that resulted postponed as compared to more fertile environments thus ensuring a longstanding soil protection from soil erosion. In addition, the higher nitrogen fertilization dose (100 kg ha−1 of N) allowed interesting biomass yield as compared to the lower dose (50 kg N ha−1) and kept constant SOC along the year of experimentation due to an improved contribution of leaf fall, root exudates and root turnover to soil. o.

Light and nitrogen are the main factors commanding horticulture production. Therefore, this study aims at evaluating the effects of two different greenhouse cover films (clear-Film A and diffuse light-Film B) on yield and nutritive value of a ready-to-eat salad lamb’s lettuce (Valerianella locusta L.), grown under several nitrogen regimes (no nitrogen [N0], sub-optimal [N25] and optimal N fertilization [N50] corresponding to 0, 25 and 50 kg ha-1 , respectively). The combination N50 and Film B boosted SPAD index by 10.3% and yield by 91.9% compared to N0 × Film A. Concerning antioxidant activity and bioactive compounds, only total ascorbic acid was positively affected by Film B (9.4%), while there was no effect of this cover film on carotenoids and chlorophyllous pigments, which increased along the increment of nitrogen rates. Nitrate content in leaves was influenced by both factors and it showed increasing values, when nitrogen doses increased, reaching the highest value under N50-Film B conditions (3312.3 mg kg-1 fw). Our study showed that in the Mediterranean area, the use of greenhouse diffuse light film improved lamb’s lettuce yield, but on the other hand incurred significant increase in nitrate level, nonetheless remaining constantly under the legal threshold imposed by the commission regulation (EU). Secondary metabolites, such as total phenols and carotenoids, showed similar values under both films, instead the diffuse light film improved total ascorbic acid content.

With the perspective of reintroducing peanut cultivation in southern Italy about six decades after its dismissal, research was carried out with the aim to identify the best performing farming management in terms of yield and quality. In this respect, the effect of the factorial combination between four plant densities (6.1, 7.8, 10.3, and 12.1 plants m-2) and two harvest times (100 and 110 days after planting) was assessed on pod and seed yield, as well as on seed quality, antioxidant activity, and elemental composition. The later harvest time determined a 26.9% dry weight increase, but a 14.3% decrease in the number of seeds per pod. Plant density significantly influenced all the yield and growth indices except for mean seed weight. Yield and growth of each plant were best affected by the lowest plant density, whereas the opposite trend was recorded for the same parameters referred to the surface area unit. The density of 12.1 plants m-2 resulted in a 32% reduction in pods per plant compared to 6.1 plants m-2, but had the greatest effect on seed production per m-2. The leaf area index was the highest with the density of 12.1 plants m-2. The total dry weight increased by 1.7-fold from 6.1 to 12.1 plants m-2. Compared to the first harvest time, in the second one the protein content decreased by 6.8%, and total polyphenols and antioxidant activity decreased by 11.2% and 7.6%, respectively. The second harvest time led to a depletion of N, P, and Mg, by 6.8%, 6.2%, and 6.8%, respectively, and a 7.1% Ca increase. The reintroduction of peanut cultivation in southern Italy is a realistic goal, though further studies regarding the crop system management are needed.

Since the early 1980s, the AVHRR sensor on board the NOAA satellites has provided SST estimates to the scientific community in general. Towards the end of the 1990s, a new generation of radiometers was added, combining a wider range of spectral measurements with improvements in technology, such as the MODIS sensor on board the Terra and Aqua satellites. The development of this last sensor was based on the years of NOAA/AVHRR series. Understanding the relationship between products derived from different sensors is critical to the continuous long-term monitoring of any variable and the construction of continuous time series. The objective of this work was to make a comparison of the monthly SST values for the 2003-2006 period calculated from data from the NOAA/AVHRR series versus Aqua-MODIS on a sector of the middle Argentina Continental shelf off the San Jorge Gulf. For both sensors, the isotherms show a similar distribution pattern in all months. Pearson’s correlation coefficient was high, both in the seasonal (> 0.9) and monthly (> 0.8) analyzes. The comparative analysis of the temperature estimated by both sensors shows that SST products are similar and can be used to analyze large and continuous time series. Fil: Allega, Leticia. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Cozzolino, E.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina Fil: Pisoni, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Piccolo, Maria Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur; Argentina

The analysis concerns data from the Northern Italian Seronegative Drug Addicts Study, a multicenter longitudinal study about the incidence of human immunodeficiency virus infection in intravenous drug users from Milan and other areas of northern Italy between 1987 and 1991. Different measures of parenteral and heterosexual exposure effects were estimated by fitting multiplicative models for rate ratio and additive models for both rate ratio and rate difference into a Poisson regression model for grouped cohort data. In areas of high human immunodeficiency virus prevalence among intravenous drug users, the adjusted rate ratio under a multiplicative structure was 6.2 (95% likelihood-based confidence interval (LCI) 2.9-14.4) for parenteral and 2.9 (95% LCI 1.3-6.1) for sexual transmission. Under the additive model, the rate ratio was 7.8 (95% LCI 3.4-20.2) for parenteral and 9.2 (95% LCI 2.2-29.7) for sexual transmission, and the rate difference per 100 person-years was 9.8 (95% LCI 5.3-15.6) for parenteral and 10.5 (95% LCI 1.8-24.2) for sexual transmission (controlled for each other). Because of the small sample size, a clear discrimination between models could not be reached. However, in spite of the greater risk associated with parenteral transmission under a multiplicative model, the additive model suggests that the relative impact of measures aimed at inducing condom use is similar to that which would be obtained by measures aimed at stopping syringe sharing.