Experimental Study on the Mechanical Properties of Friction, Collision and Compression of Tiger Nut Tubers

The mechanical properties of agricultural materials can provide the basis for the design and optimisation of agricultural machinery. There are currently very few studies on the mechanical properties of tiger nut tubers, which is not conducive to the design and development of machinery for their harvesting and processing. To obtain the mechanical parameters of tiger nut tubers, this study investigated the effects of variety (Zhong Yousha 1 and Zhong Yousha 2), moisture content (8%, 16%, 24%, 32% and 40%), contact material (steel, aluminium, plexiglass and polyurethane), release height (170 mm, 220 mm, 270 mm and 320 mm), loading speed (5 mm/min, 10 mm/min, 15 mm/min and 20 mm/min), compression direction (vertical and horizontal) on the friction, collision and compression mechanical properties of the tubers. The results were as follows: Both moisture content and contact material had a significant effect (p < 0.01) on the sliding friction coefficient (0.405–0.652) of the tubers; both variety and moisture content had a significant effect (p < 0.01) on the angle of repose (27.96–36.09°); contact material, moisture content, release height and variety all had a significant effect (p < 0.01) on the collision recovery coefficient (0.376–0.672) of tubers; variety, loading speed, moisture content and compression direction all had significant effects (p < 0.01) on the damage force (87.54–214.48 N), deformation (1.25–6.12 mm) and damage energy (82.38–351.08 mJ) of the tubers; only moisture content and compression direction had significant effects (p < 0.01) on the apparent elastic modulus (12.17–120.88 MPa) of the tubers. The results of this study can provide a reference for the design and optimisation of machinery for the harvesting and processing of tiger nut tubers.

Evaluation of the technical capacity of artisans to fabricate the animal-powered direct seeder super-eco in Sénégal.

This study focused on the ability of local Senegalese artisans to fabricate the animal-powered no-till (NT) direct seeder Super-Eco to reduce the expensive import of seeders. Technical specifications and design of the animal-powered direct seeder Super-Eco were first given to 90 heads of artisanal workshops in three regions of the Southern Peanut Basin for them to reproduce the machine. Detailed information on their workshop equipment was collected in advance. A principal component analysis (PCA) was then used to classify artisan workshops. The results showed that Class 3 was very well equipped and was able to fabricate the direct seeder. It was followed by Class 2 which was fairly well equipped, but was only able to develop 90% of the seeder parts. Because of a low level of equipment, the third class of artisans was only capable of fabricating very few pieces of the seeder. Artisans from Class 3 were able to fully construct the animal-powered direct seeder. However, it was noted that the other classes of artisans were able to reproduce some parts of the animal-powered direct seeder Super-Eco but they could not make the seeder box with its nested seed metering device due to their low level of equipment. They instead buy it from the Sahelian Industrial Company of Mechanics, Agricultural Materials and Representations or from traders. The need to evaluate the performance of the seeders developed by local artisans is also noted.

Control Efficacy of Bacillus velezensis AFB2-2 against Potato Late Blight Caused by Phytophthora infestans in Organic Potato Cultivation

Although late blight is an important disease in eco-friendly potato cultivation in Korea, it is highly dependent on the use of eco-friendly agricultural materials and the development of biological control technology is low. It is a necessary to develop an effective biocontrol agent to inactivate late blight in the field. AFB2-2 strain is a gram-positive with peritrichous flagella. It can utilize 20 types of carbon sources, like L-arabinose, and D-trehalose at 35°C. The optimal growth temperature of the strain is 37°C. It can survive at 20-50°C in tryptic soy broth. The maximum salt concentration tolerated by AFB2-2 strain is 7.5% NaCl. AFB2-2 strain inhibited the mycelial growth of seven plant pathogens by an average inhibitory zone of 10.2 mm or more. Among the concentrations of AFB2-2, 107 cfu/ml showed the highest control value of 85.7% in the greenhouse. Among the three concentrations of AFB2-2, the disease incidence and severity of potato late blight at 107 cfu/ml was lowest at 0.07 and 6.7, respectively. The nucleotide sequences of AFB2-2 strain were searched in the NCBI GenBank; Bacillus siamensis strain KCTC 13613, Bacillus velezensis strain CR-502, and Bacillus amyloliquefaciens strain DSM7 were found to have a genetic similarity of 99.7%, 99.7%, and 99.5%, respectively. The AFB2-2 strain was found to harbor the biosynthetic genes for bacillomycin D, iturin, and surfactin. Obtained data recommended that the B. velezensis AFB2-2 strain could be considered as a promising biocontrol agent for P. infestans in the field.

ANALYTICAL REVIEW OF TECHNICAL SOLUTIONS OF NEEDLE ROTARY TOOLS FOR APPLYING LIQUID FERTILIZERS TO THE SOIL LAYER

The purpose of the research is to identify trends in the technical development of needle rotary means for injecting liquid mixtures into the soil layer, taking into account the essence of the technological operation, as a control action to change the state of the soil. Research methods - analysis and generalization of essential features of technical solutions of needle tools for processing and applying liquid fertilizers to the soil layer. In order to develop criteria for evaluating technical solutions, scientific research on the classification of tools of this type and generalized interpretations of the essence of technological operations of tillage, application of chemicals, sowing, etc. were preliminary analyzed. Research results. An analysis from the point of view of the possibility of controlling the process and the degree of its implementation by a specific instrument allows to assess the place of a specific tool in the development stage. In accordance with the "System of properties and indicators of soil condition" [Vetokhin 2009], any introduction / extraction of matter, energy and / or information is considered a controlling factor in changing the state of the system, the ultimate goal of which is to change the level of metabolic processes and, as a result, to change the yield. An increase in the information component of processes is considered to be a tendency in the development of agricultural technologies and technical means aimed at a radical reduction in resource consumption [Vetokhin, Altybaev 2019]. One of the first technical solutions of needle tools for applying liquid to the soil layer is known from the American patent of 1898 [Morris, 1898]. The aim of the inventor is to provide a device adapted to form a hole in the soil for receiving a plant and supplying water to the hole. The current state of the development of technical means is illustrated by the invention, patented in the USA, RF and EU, "Systems, methods and devices for the introduction of agricultural liquids" [Stoller et al., 2020], [Radtke et al., 2020], [Levy et al., 2015]. A qualitatively new level is achieved by the inclusion of sensors of the current state of the soil in the process control system. Sensors come in contact with the soil to monitor its condition, in particular, density, temperature, humidity, percentage of carbon, organic matter, potassium, phosphorus, nitrogen, etc. In a fluid delivery system, each of the outlets is connected to separate sources of input material and may contain dissimilar fluid materials, for example, different types of fertilizers, liquid insecticides. Conclusions. It has been established that the technical solutions of needle tools have been developed from manual devices of periodic action to rotary needle tools of continuous action for dosed application of complex fertilizers and simultaneous loosening of the soil. The next step in technical development is to expect the creation of automated complexes with rotary needle working bodies, which are able to continuously assess the condition of the soil and control the process of loosening and applying agricultural materials with different doses along each row. A promising stage of technical and technological development is the creation of means that will directly control metabolic processes in a system with a layer of soil. In a scientific sense, the study of trends in the development of technical means confirmed the previously published theoretical generalization of soil properties in relation to the process of managing its condition with minimal resource costs.

Optimal Versus Equal Dimensions of Round Bales of Agricultural Materials Wrapped with Plastic Film—Conflict or Compliance?

For the assumed bale volume, its dimensions (diameter, height), minimizing the consumption of the plastic film used for bale wrapping with the combined 3D method, depend on film and wrapping parameters. Incorrect selection of these parameters may result in an optimal bale diameter, which differs significantly from its height, while in agricultural practice bales with diameters equal or almost equal to the height dominate. The aim of the study is to formulate and solve the problem of selecting such dimensions of the bale with a given volume that the film consumption is minimal and, simultaneously, the bale diameter is equal or almost equal to its height. Necessary and sufficient conditions for such equilibria of the optimal bale dimensions are derived in the form of algebraic equations and inequalities. Four problems of the optimal bale dimension design guaranteeing assumed equilibrium of diameter and height are formulated and solved; both free and fixed bale volume are considered. Solutions of these problems are reduced to solving the sets of simple algebraic equations and inequalities with respect to two variables: integer number of film layers and continuous overlap ratio in bottom layers. Algorithms were formulated and examples regarding large bales demonstrate that they can handle the optimal dimensions' equilibria problems.

Near-Infrared Spectroscopy and Machine Learning: Analysis and Classification Methods of Rice

Nowadays, the conventional biochemical methods used to differentiate and characterize rice types, biochemical properties, authentication, and contamination issues are difficult to implement due to the high cost of reagents, time requirement and environmental issues. Actually, the success of agri-food technology is directly related to the quality of analysis of experimental data acquired by sensors or techniques such as the infrared-spectroscopy. To overcome these technical limitations, a rapid and non-destructive methodology for discrimination and classification of rice has been investigated. Near-infrared spectroscopy is considered as fast, clean, and non-destructive analytical tools and its spectra present significant biomolecular information that must be analysed by sophisticated methodologies. Machine learning plays an important role in the analysis of the spectral data being used several methods such as Partial Least Squares, Principal Component Analysis, Partial Least Squares-Discriminant Analysis, Support Vector Machine, Artificial Neuronal Network, among others which can successfully be applied for food classification and discrimination as well as in terms of authentication and contamination issues. The quality control of rice is extremely important at every stage of production, beginning with estimation of raw agricultural materials and monitoring their quality during storage, estimating food quality during the production process and of the final products as well as the determination of their authenticity and the detection of adulterants.

Accumulation, risk assessment and source apportionment of heavy metals in protected cultivation soil, China

The problem of soil heavy metals (HMs) accumulation from protected cultivation (PC) needs an urgent solution. 132 soil samples from typically high-density PC areas were analyzed for accumulation, risk, and sources of 8 HMs in 16 cities of 8 provinces, China. The soil HMs accumulation characteristics were prominent; Cu, Zn, Pb, Cd, As over-standard (GB 15618-2016) rates reached 15.2, 4.5, 3.0, 27.3, and 2.3%, respectively. The single-factor pollution index indicates that Cd reached slightly contaminated levels in the whole area, while Cu was at a slightly contaminated level only in Yunnan Province. The Nemeiro comprehensive pollution index and the comprehensive quality index suggested that HMs accumulation were at the slightly contaminated levels, with Yunnan province being the most affected and Henan followed. Cu and Zn accumulations are mainly related to frequent input of organic fertilizer, especially livestock manure’s direct return to the field. Therefore, Cu and Zn showed a strong correlation (P＜0.01) with soil organic material (SOM), and their available amounts linearly correlated with the extension of planting years in PC. On the contrary, Pb and Cd amounts are only related (P＜0.01) to soil texture, and their main sources are related to the parent material of soil formation. Moreover, their available amounts did not correlate with the planting years. Our results suggest that long-term and unreasonable PC may lead to soil HMs accumulation. Therefore, appropriate agricultural materials, planting systems, and fertilization methods must be used to effectively avoid the risk of excessive HMs accumulation in the PC soils.