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Machine learning is a widespread technology that plays a crucial role in digitalisation and aims to explore rules and patterns in large datasets to autonomously solve non-linear problems, taking advantage of multiple source data. Due to its versatility, machine learning can be applied to agriculture. Better crop management, plant health assessment, and early disease detection are some of the main challenges facing the agricultural sector. Plant phenotyping can play a key role in addressing these challenges, especially when combined with machine learning techniques. Therefore, this study reviews available scientific literature on the applications of machine learning algorithms in plant phenotyping with a specific focus on sunflowers. The most common algorithms in the agricultural field are described to emphasise possible uses. Subsequently, the overview highlights machine learning application on phenotyping in three primaries areas: crop management (i.e., yield prediction, biomass estimation, and growth stage monitoring), plant health (i.e., nutritional status and water stress), and disease detection. Finally, we focus on the adoption of machine learning techniques in sunflower phenotyping. The role of machine learning in plant phenotyping has been thoroughly investigated. Artificial neural networks and stacked models seems to be the best way to analyse data. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of the temperature and reaction time variables on the solid yield and the increment of heating values and composition of torrefied Dichrostachys cinerea wood by using a factorial experiment design and thermogravimetric analysis. The significant factors were identified by means of a two-level factorial design type (2), for which the statistical software Design Expert version 10 was used. Torrefaction and thermogravimetric experimental runs were carried out in a fixed-bed reactor and thermobalance TGA-DTA, respectively. Torrefaction temperature, residence time and their interaction have a significant effect on solid yield, whilst the effect of the temperature was the only statistically significant factor on increment at a high heating value (HHV). The R-Squared values for both response variables were greater than 95% in each case. An increase in torrefied biomass was achieved at HHVs of 14.92 and 30.31% under the conditions of 120 min at 250 and 290 °C, respectively. Thermogravimetric characterisation and DTG-TG curves of the torrefied material suggest that the pre-treated material has been modified chemically and structurally. [ABSTRACT FROM AUTHOR]

Currently the biodiesel chain is promoted by the European energy policy. For the Italian scenario the sunflower is one of the most important crop to be considered for biodiesel production but the chain is not fully profitable. This problem could be solved with the increase of farm incomes through a proper valorization of by-products. From this point of view the oilseed crop is not considered only for oil production but also for producing multiple products with the same economic value. This is the main inspiring concept of the Extravalore project. The sub-project “Raw Materials” investigated about the possible influence of different agro-technics performed in three distinct geographical environments (Northern, Central and Southern Italy) on the characteristics of by-products obtained from sunflower crop. A national net of experimental tests was set during the 2010–2013 period in order to evaluate the adaptability and the potential production of high oleic sunflower hybrids. 7 seed companies supplied the 20 genotypes assessed in total (18 high oleic hybrids and 2 as control), 11 of them were evaluated all the three years. Achene yields of tested high oleic hybrids were extremely variable: from 2.05 t ha −1 to 4.04 t ha −1 in Northern Italy, from 2.50 t ha −1 to 4.24 t ha −1 in Central Italy and from 2.09 t ha −1 to 2.68 t ha −1 in Southern Italy. For this reason, it was necessary a precise characterization of varieties before their cultivation. The cultivar screening showed general difficulty for high oleic hybrids to reach the performances of achene and oil yields of the conventional ones. In particular, LG55.57HO and PR64H31 resulted the best high oleic cultivars for Northern Italy; many of the high oleic tested cultivars performed well for Central Italy and also for Southern Italy but with a higher variability. The highest potential production was registered in Central Italy; Northern Italy gave decreased but similar results, despite the different latitude; in Southern Italy the productions were 20–30% lower, even with the irrigation support. All high oleic tested cultivars showed oleic acid content in lipid fraction always above the 84% in Central Italy, meaning a stability of the character, very important for the biodiesel production. [ABSTRACT FROM AUTHOR]

• Sunflower is an important oilseed crop affected by environmental and geopolitical threats. • Sunflower can be managed with advanced agriculture techniques thanks to its high mechanizability. • Remote sensing is widespread in the agricultural sector, but it is not so for sunflowers. • Most of the studies on the application of remote sensing do not involve the world's major producers. • The evaluated topics are: vegetation indices, forecasting and growth models, abiotic stresses. Sunflower is an annual species of the Asteraceae family, and it occupies a relevant position in the world market business as one of the most important oilseed crops. Given the current geopolitical situation and climate change, the agri-food supply chain of sunflower is in crisis. In this context, precision agriculture, especially remote sensing, can address demands for more production and greater sustainability. The aim of the present systematic review is to evaluate the available scientific literature on precision agriculture applied to sunflower crop, specifically the use of hyperspectral data to calculate vegetation indices or create crop growth models. The systematic review follows specific guidelines and a well-described review protocol. A total of 104 studies were included in the review, starting from raw search in different data sources (Scopus, Web of Science, Springer Link, and Science Direct) and following with the application of inclusion criteria. Results focused on the following main topics: crop management (i.e., management zones, yield prediction, vegetation indices correlations), sunflower crop growth monitoring (i.e., identify different growth stages and vegetation parameters), weed management, and industrial applications. The role of hyperspectral sensors has been thoroughly investigated to help choose ideal wavelengths related to vegetation indices. Future research should prioritise water stress management, time-saving evaluation of new sunflower hybrids, and crop growth models. [ABSTRACT FROM AUTHOR]

• Post-digestate composting effect on removal of ARGs was investigated. • tet (M) was the most abundant ARG in fresh digestate compared to other ARGs. • After 90 days of composting, ARGs abundance was reduced by more than 80%. • Actinobacteria, Planctomycetes, and Verrucomicrobia succeeded with composting. • Arenibacter and Cellvibrio were potential hosts for ARGs. Post-digestate treatments may reduce the risk linked to Antibiotic Resistant Genes (ARGs) release with digestate direct land application. Thus, this study aimed to evaluate post-digestate composting and co-composting with biogas production feedstock (maize silage, food processing waste, and poultry litter) effect on abundance of selected ARGs: erm (B), tet (K), tet (M), tet (O), and tet (S) genes. More than 80% of all ARGs were removed after 90 days of composting but removals from co-composting were lower. Bacteroidetes, Firmicutes, and Proteobacteria dominated fresh digestate, and a network analysis indicated that these were potential hosts of ARGs. The emergence of Actinobacteria (dominant), Planctomycetes, and Verrucomicrobia phyla during composting shifted the microbial composition. Moreover, canonical correspondence analysis showed trace elements explaining 90% variations in ARGs abundance. The study illustrates significance of post-digestate composting in mitigating ARGs release, and effectiveness could be linked to shift in microbial composition and trace elements release. [ABSTRACT FROM AUTHOR]

The Extravalore project aims to give added value to oilseed crops, considering them also for producing multiple products with the same economic value and being interesting for the market thanks to their various utilizations. An evaluation of the main cultivars of Brassica napus subsp. oleifera and Brassica carinata has been performed within the project, analyzing them in three Italian locations with different climatic conditions (Palazzolo dello Stella – North Italy, Osimo – Central Italy, Cassibile – South Italy) to assay their adaptability and production potential. During the 2010–2013 period, 43 varieties of rapeseed were evaluated, but only 13 of them for all the period considered; moreover, also 4 varieties of B. carinata were tested. The seed yields of tested cultivars of rapeseed varied a lot among locations, depending also by the seasonal trend. Central Italy was the less disadvantaged by climatic conditions: on average, it was reached a seed yield of 4 t ha −1 , a theoretical oil production of 1.63 t ha −1 and more than 8 t ha −1 of crop residues. In Northern and Southern Italy, if compared with Central Italy values, the seed yields were both lower than 30% and theoretical oil productions lower than 60%; moreover, crop residues in Northern Italy were 12% lower than in Central Italy while in Southern Italy 65% lower. The agronomic behavior of varieties differed a lot among the three experimental areas: DK Expower was the best at North; Albatros, Artoga, Exagone and Excalibur in Central Italy; Excalibur, Zoom and PR46W14 at South Italy but none of them reached a seed yield of 2 t ha −1 . Concerning B. carinata , the cultivars did not give good productions in any of the experimental areas, mainly because of the low oil content in the seeds. Even in Central Italy, where the best results were registered, the seed yield was on average 28% lower than in rapeseed and oil production 10% lower; the crop residues were double than rapeseed. In any case, the valorization of the crop residues is important with a wide range of possible utilization from the direct energetic use to the biochemicals extraction with consequent environmental advantages due to the substitution of dedicated or fossil feedstock with crop residues. [ABSTRACT FROM AUTHOR]

Abstract: Tomato manufacturing industry originates substantial amounts of residues. If left without control these residues can constitute an environmental problem. Their energetic use can solve this problem and give added value to the process. In this research physical-chemical characteristics of this biomass and its components are studied to evaluate the possibility of an energy recovery. In general, the dry residues of tomato processing industry are suitable as solid biofuel for energy purposes in large size power plants. The separation of components that constitute tomato residues (peels and seeds) makes sense in case of production and exploitation of oil from tomato seeds. The results can be useful for developing standards on these materials. [Copyright &y& Elsevier]

[Display omitted] • Pilot level aerobic co-composting of digestate and biogas feedstocks was conducted. • Composting reduced C/N ratio, release of trace elements, and phytotoxicity. • Enzyme activities were influenced by OM content and release of trace elements. • Enzyme activities could be compost maturity indicators. The current study evaluated the quality of agricultural waste digestate by composting or co-composting with biogas feedstock (maize silage, food processing waste, or poultry litter). Temperature, phytotoxicity, C/N ratio, water extractable trace elements, and 14 enzyme activities were monitored. Temperature dropped earlier in digestate and maize silage co-composting pile, reducing time to maturity by 20 days. Composting and co-composting reduced phytotoxicity and C/N ratio, but increased immobilization of Al, Ba, Fe, Zn, and Mn at least by 40% in all piles. All the enzyme activities, except arylsulfatase and α-glucosidase, increased at the maturity phase and negatively correlated with organic matter content and most of trace elements. Post-digestate composting or co-composting with biogas feedstock is a promising strategy to improve digestate quality for fertilizer use, and selected enzyme activities can be indicators of compost maturity and immobilization of trace elements. [ABSTRACT FROM AUTHOR]

This study focuses on verifying the influence of some additives in the ash melting process of herbaceous biomass, developing a pelletized biofuel from the mixture of herbaceous biomass and various inorganic substances through a series of experimental tests. Therefore, different materials were sampled, chemically characterized and combined in mixtures of low-melting biomass materials. Tests were performed with various inorganics products added directly on the relative ashes to verify the interaction between the two systems. Subsequently, herbaceous biomass pellets containing growing amounts of additive were produced, verifying their effectiveness by analyzing the ash melting temperatures and adopting the PASSA test, that investigates the size of the ashes after incinerating the biomass in a muffle. The same method was then used to evaluate the ashes of an industrial boiler. Results show that the addition of inorganic additives in the extent of 3–5% by weight determines an increase in deformation temperatures over 547 °C for several biomass materials and additives. Tests carried out on forage pellets made with alfalfa and CaO as additive brought instead to an increase in deformation temperature between 43 and 107 °C. This work could be of interest in the evaluation of the energy reuse of herbaceous materials that would otherwise be considered as waste, and also it suggests the possibility of using egg shells as inorganic additives in accordance to the circular economy approach. Furthermore, the additivation level of these pelletized biofuel is perfectly in line with the provisions of ISO 17225-6 for non-woody pellets (≤5% weight). [ABSTRACT FROM AUTHOR]