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90–102 V. Bulgakov, I. Savchenko, I. Holovach, P. Rykhlivskyi, J. Olt and Ye. Ihnatiev
Study of finger-star disc working tools of an inter-row cultivator
Abstract |

Study of finger-star disc working tools of an inter-row cultivator

V. Bulgakov¹, I. Savchenko², I. Holovach¹, P. Rykhlivskyi², J. Olt³* and Ye. Ihnatiev³⁴

¹National University of Life and Environmental Sciences of Ukraine, 15, Heroyiv Oborony Str., UA 03041 Kyiv, Ukraine
²Institute of Mechanics and Automatics of Agroindustrial Production of the National Academy of Agrarian Sciences of Ukraine, 11/1, Vokzalna Str., UA 08631 Hlevakha, Ukraine
³Estonian University of Life Sciences, Institute of Forestry and Engineering, 56 Kreutzwaldi Str., EE 51006 Tartu, Estonia
⁴Dmytro Motornyi Tavria State Agrotechnological University, 66 Zhukovsky Str., UA 69600 Zaporizhzhia, Ukraine
*Correspondence: jyri.olt@emu.ee

Abstract:

This study combines laboratory force-deflection characterization, tomato transplant pull-out measurements and a descriptive field verification of an inter-row cultivator equipped with polyurethane finger-star discs. The objective was to relate finger hardness to crop mechanical resistance and thereby define a practical screening criterion for reducing crop damage. Discs with hardness values of 73, 83 and 93 Shore A were loaded at finger deflections from 0 to 50 mm. Pull-out force was measured for individual established tomato transplants at MG-44 instrument-reported relative soil-moisture readings of 18% (n = 5) and 10% (n = 7) in the 0–100 mm layer. The force–deflection relationships were linear (R2 = 1.000), and transplant pull-out force increased linearly with stem diameter (R2 = 0.991–0.994). During field operation at a working width of 4.2 m, travel speed of 1.0–2.0 m s–1 and disc working depth of 1.5–5.0 cm, complete visible destruction was observed for weeds at the white-thread stage and no visible injury to established tomato plants was recorded. These field proportions were obtained in a non-randomized engineering verification and are therefore descriptive. Within the tested range, 73, 83 and 93 Shore A discs are provisionally recommended for crops with pull-out forces of at least 10, 15 and 25 N, respectively. An Euler–Bernoulli cantilever-beam analysis explains the observed linear response and identifies the contact conditions that favour finger sliding rather than crop displacement.

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96-113 S.G. Mohammed, H. Maaroufi Dguimi, S.H. Bashir, S.A. Tammam, H. Abdalgadir, S.M. Howladar and F.O. Alzahrani
Phytochemical screening and evaluation of antioxidant and antimicrobial activity of Solanum incanum: medicinal plant from Al-Baha Region
Abstract |
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Phytochemical screening and evaluation of antioxidant and antimicrobial activity of Solanum incanum: medicinal plant from Al-Baha Region

S.G. Mohammed¹², H. Maaroufi Dguimi¹*, S.H. Bashir¹³, S.A. Tammam⁴, H. Abdalgadir¹, S.M. Howladar⁵ and F.O. Alzahrani¹

¹Al-Baha University, Faculty of Science, Department of Biology, Al-Baha, Saudi Arabia
²University of Khartoum, Faculty of Science, Department of Botany, Khartoum, Sudan
³Bahri University, Collage of applied and industrial Sciences, Department of Chemistry, Sudan
⁴Assiut University, Assiut, Faculty of Science, Department of Botany, Assiut, Egypt
⁵University of Jeddah, College of Sciences, Department of Biological Sciences, Jeddah, Saudi Arabia
*Correspondence: houda_maaroufi@yahoo.fr

Abstract:

Solanum incanum is a prominent medicinal plant, used to treat various ailments. The current study sought to assess the phytochemical profile, as well as the antioxidant and antimicrobial activities, of the crude methanolic extract and the corresponding chloroform, ethyl acetate, n-hexane, and aqueous fractions of the leaves, stem bark, and fruits. Leaf and fruit extracts had the largest levels of polyphenols, flavonoids, tannins, and alkaloids referring to stem-bark. Hexadecanoic acid methyl ester is a major phytochemical component revealed in different plant parts, especially in stem-bark with 31.82% level. The 9,12,15-Octadecatrienoic acid, methyl ester is also revealed in all plant parts, especially in leaf with 20.07%. Fruit and leaf ethyl acetate and water fractions showed the highest antioxidant capacity compared to stem-bark fractions. Using the agar disc diffusion method, antimicrobial activity was evaluated in vitro against four different bacterial species and one fungal species (Candida albicana). The ethyl acetate, n-hexane, and chloroform fractions of fruits and leaves showed strong antimicrobial activity against all microorganisms. Aqueous fraction of different plant parts was inactive or partially active against tested microorganisms. The high total content of phenols, flavonoids, tannins and alkaloids, especially in leaves and fruits, correlates positively with the highest antimicrobial and antioxidant activities detected in these parts of the plant.

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