Effect of Spraying Glyphosate Herbicide on Solanum elaeagnifolium in Uncultivated Fields and on Physicochemical and Biological Soil Characteristics

Bakkour, F., A. El-Meamar and Z. El-Naser. 2021. Effect of Spraying Glyphosate Herbicide on Solanum elaeagnifolium in Uncultivated Fields and on Physicochemical and Biological Soil Characteristics. Arab Journal of Plant Protection, 39(4): 296-308. https://doi.org/10.22268/AJPP-39.4.296308 Glyphosate herbicide is used in uncultivated fields infested with Solanum elaeagnifolium plants several times a year in all Syrian governorates by the Ministry of Agriculture. This research aimed to study the effect of repeated spraying of glyphosate in uncultivated fields in five different locations in the Syrian governorates, Deir Ezzor (Tebni), Aleppo (Dakwani), Hama (Bostan AL-Omahat), Homs (ALZahoria) and Rural Damascus (Bohter) during the period 2017-2020, on the physiochemical and biological characteristics of the treated soils. Herbicide residues were measured in the leaves of the treated Solanum elaeagnifolium plants and in the soils surrounding the roots of the Solanum elaeagnifolium plants. It was found that the repetition of the pesticide spray 3 and 6 times during the study period did not alter the physical composition, salinity, pH and calcium carbonate content in all study locations. Whereas, spraying glyphosate 3 and 6 times increased the percentage of organic matter and phosphorus available, with a significant difference with the control. The values of available phosphorous after 6 pesticide spray applications reached 176, 203, 196, 227 and 205 mg/kg of soil in Deir Ezzor, Aleppo, Hama, Homs and Rural Damascus, respectively. In addition, repeated spraying with glyphosate of the treated soils led to increase the average general bacteria and fungi populations. These indicators were increased with the increase in the number of pesticide sprays applied. Furthermore, the pesticide residues increased in the soil and Solanum elaeagnifolium leaves with the increase in number of pesticide sprays. Pesticide residue values after 6 sprays were 1.72, 3.53, 4.89, 4.43 and 2.29 mg/kg of soil in Deir Ezzor, Aleppo, Hama, Homs and Rural Damascus locations, respectively. Keywords: Glyphosate, S. elaeagnifolium, residues, microorganisms, soil.

Examining the Role of Buzzing Time and Acoustics on Pollen Extraction of Solanum elaeagnifolium

Buzz pollination is a specialized pollination syndrome that requires vibrational energy to extract concealed pollen grains from poricidal anthers. Although a large body of work has examined the ecology of buzz pollination, whether acoustic properties of buzz pollinators affect pollen extraction is less understood, especially in weeds and invasive species. We examined the pollination biology of Silverleaf nightshade (Solanum elaeagnifolium), a worldwide invasive weed, in its native range in the Lower Rio Grande Valley (LRGV) in south Texas. Over two years, we documented the floral visitors on S. elaeagnifolium, their acoustic parameters (buzzing amplitude, frequency, and duration of buzzing) and estimated the effects of the latter two factors on pollen extraction. We found five major bee genera: Exomalopsis, Halictus, Megachile, Bombus, and Xylocopa, as the most common floral visitors on S. elaeagnifolium in the LRGV. Bee genera varied in their duration of total buzzing time, duration of each visit, and mass. While we did not find any significant differences in buzzing frequency among different genera, an artificial pollen collection experiment using an electric toothbrush showed that the amount of pollen extracted is significantly affected by the duration of buzzing. We conclude that regardless of buzzing frequency, buzzing duration is the most critical factor in pollen removal in this species.

Structural Dynamics of Real and Modeled Solanum Stamens: Implications for Pollen Ejection by Buzzing Bees

An estimated 10% of flowering plant species conceal their pollen within tube-like anthers that dehisce through small apical pores (poricidal anthers). Bees extract pollen from poricidal anthers through a complex motor routine called floral buzzing, whereby the bee applies large vibratory forces to the flower stamen by rapidly contracting its flight muscles. The resulting deformation and pollen expulsion depend critically on the stamen's natural frequencies and vibration mode shapes, yet these properties remain unknown. We performed experimental modal analysis on Solanum elaeagnifolium stamens to quantify their natural frequencies and vibration modes. Based on morphometric and dynamic measurements, we developed a finite element model of the stamen to identify how variable material properties, geometry and bee weight could affect its dynamics. In general, stamen natural frequencies fell outside the reported floral buzzing range, and variations in stamen geometry and material properties were unlikely to bring natural frequencies within this range. However, inclusion of bee mass reduced natural frequencies to within the floral buzzing frequency range and gave rise to an axial-bending vibration mode. We hypothesize that floral buzzing bees exploit the large vibration amplification factor of this mode to increase anther deformation, which may facilitate pollen ejection.

Plant-Mediated Biological Synthesis of Ag-Ago-Ag2O Nanocomposites Using Leaf Extracts of Solanum Elaeagnifolium for Antioxidant, Anticancer, and DNA Cleavage Activities

The biogenic nanocomposite synthesis using a plant extract is rapid, simple, efficient, cost-effective, and eco-friendly. This study investigated selective pharmacological activities such as anticancer, antioxidant, and DNA cleavage activities of Solanum elaeagnifolium-mediated green synthesizing Ag-AgO-Ag2O nanocomposite. To the best of our knowledge, Solanum elaeagnifolium has been the first time used to synthesize Ag-AgO-Ag2O nanocomposites. The synthesized nanocomposites were explored by using UV-Vis diffuse reflectance spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and photoluminescence analyses. Anticancer activity of Ag-AgO-Ag2O nanocomposites was tested on lung cancer cell lines (A-549) and showed activity at the IC50 of 67.09 μg/mL. The maximum ABTS and DPPH scavenging activity were 25.78% and 20.86% at 100 µg/L, respectively. Moreover, Solanum elaeagnifolium-mediated green synthesized Ag-AgO-Ag2O nanocomposites also exhibited considerable DNA cleavage activity. These results assured that the synthesized Ag-AgO-Ag2O nanocomposites using Solanum elaeagnifolium leaves extract may have potential applications in biomedical engineering.

Nuevos registros de taxones de interés corológico para la flora vascular de la provincia de Córdoba (Andalucía occidental, España).

Se aportan nuevos registros de varios taxones de flora vascular, tanto autóctonos como alóctonos naturalizados, de interés corológico: Vachellia farnesiana (L.) Wight & Arn. (novedad para Andalucía occidental), Astragalus boeticus L. (novedad para la Vega), Cullen americanum (L.) Rybd. (novedad para la Vega y Sierra Norte, en la zona de transición entre ambas), Solanum elaeagnifolium Cav. (novedad para la provincia de Córdoba) y Pulicaria dysenterica (L.) Bernh. (contaba con escasos registros previos, y se amplía su área de distribución conocida). Todos los pliegos testigo están depositados en el Herbario del Jardín Botánico de Córdoba.

Evaluation of Advanced Backcrosses of Eggplant with Solanum elaeagnifolium Introgressions under Low N Conditions

Selection and breeding of eggplant (Solanum melongena) materials with good performance under low nitrogen (N) fertilization inputs is a major breeding objective to reduce environmental degradation, risks for human health, and production costs. Solanum elaeagnifolium, an eggplant wild relative, is a potential source of variation for introgression breeding in eggplant. We evaluated 24 plant, fruit, and composition traits in a set of genotyped advanced backcrosses (BC2 and BC3) of eggplant with S. elaeagnifolium introgressions under low N conditions. Significant differences were found between the two parents for most traits, and a wide phenotypic diversity was observed in the advanced backcrosses, with some individuals with a much higher yield, nitrogen use efficiency (NUE), and phenolics content than the S. melongena parent. In general, the lower the proportion of S. elaeagnifolium genome introgressed in the advanced backcrosses, the higher was the general phenotypic resemblance to S. melongena. Putative QTLs were detected for stem diameter (pd4), presence of prickles in stem (ps6), leaf (pl6) and fruit calyx (pc6), fruit width (fw7), chlorogenic acid content (cg5), total phenolic acid peaks area (ph6), chlorogenic acid peak area (ca1), and phenolic acids pattern (cp1). Our results reveal that introgression breeding of eggplant with S. elaeagnifolium has a great interest for eggplant breeding, particularly for adaptation to low N conditions. These materials can potentially contribute to the development of improved eggplant varieties for a more sustainable agriculture.

Estudios citogenéticos y morfo-anatómicos comparativos entre diploides y poliploides de Solanum elaeagnifolium (Solanaceae).

Introducción y objetivos: Solanum elaeagnifolium, morfológicamente variable, se multiplica sexual- y asexualmente y es invasora en distintas partes del mundo. Se desconoce su rango de origen y como se propagó fuera de él. En Argentina existen poblaciones naturales diploides, tetraploides y hexaploides. Presenta tres linajes genéticos claramente distanciados, dos en Sudamérica con poblaciones poliploides y un tercero solo con diploides en América del Norte y áreas invadidas. Nuestro objetivo es detectar relaciones entre nivel de ploidía, linaje y procedencia con características morfológicas de las plantas y variables climáticas. M&M: Se realizaron preparados cromosómicos y mediciones de caracteres de epidermis, flor y semilla, en individuos 2x, 4x y 6x de diferente linaje y origen geográfico. Se compararon los valores medios obtenidos mediantes tests estadísticos y la similitud global se evaluó mediante análisis multivariados. Resultados: Únicamente número de estomas y masa de semillas resultaron significativamente diferentes entre niveles de ploidía: el citotipo tetraploide, presenta menor número de estomas y semillas más pesadas. Las restantes variables morfoanatómicas contribuyen a la diferenciación global de los citotipos, aunque no se comprobó que las medias variaran proporcionalmente con el aumento de ploidía. La precipitación media anual contribuye a la discriminación entre citotipos, coincidiendo la distribución occidental de los tetraploides con la diagonal árida en Argentina. Conclusiones: Las diferencias en el tetraploide no pueden atribuirse a un efecto de la poliploidización. El patrón global de datos podría explicarse por múltiples orígenes independientes de la poliploidía, plasticidad fenotípica y presiones del ambiente (temperatura, precipitaciones, distintos ensambles de polinizadores).