Application of Biosynthesized Silver Nanoparticles for the Control of Land Snail Eobania vermiculata and Some Plant Pathogenic Fungi

The land snail Eobania vermiculata is an important crop pest causing considerable damage in agriculture. The aim of the present work is to evaluate the possibilities of using silver nanoparticles (AgNPs) to control the land snail. The AgNPs have been synthesized biologically using white radish (Raphanus sativus var. aegyptiacus). The biosynthesis was regularly monitored by UV-Vis spectroscopy. X-ray diffraction spectra revealed peaks of crystalline nature of AgNPs and the transmission electron micrographs further confirmed the size of the synthesized nanoparticles ranging from 6 to 38 nm. The exposure of the snails and soil matrix to AgNPs in a laboratory experiment reduced the activity and the viability of the land snail (20% of AgNPs treated snails died) as well as the frequency of fungal population in the surrounding soil. Moreover histology and ultrastructure alterations have been found in both kidney and the digestive gland of AgNPs treated land snails. The synergistic effect of synthesized AgNPs as antifungal was evaluated and clearly revealed that AgNPs can be effectively used against various plant pathogenic fungi. The present study results may open a new avenue to use the snail as bioindicator organism of environmental pollution

Biosafe Management of <i>Botrytis</i> Grey Mold of Strawberry Fruit by Novel Bioagents

Recently, there have been urgent economic and scientific demands to decrease the use of chemical fungicides during the treatment of phytopathogens, due to their human health and environmental impacts. This study explored the biocontrol efficacy of novel and eco-friendly preen (uropygial) oil and endophytic Bacillus safensis in managing postharvest Botrytis grey mold in strawberry fruit. The preen oil (25 μL/mL) showed high antifungal activity against B. cinerea Str5 in terms of the reduction in the fungal radial growth (41.3%) and the fungal colony-forming units (28.6%) compared to the control. A new strain of Bacillus safensis B3 had a good potential to produce chitinase enzymes (3.69 ± 0.31 U/mL), hydrolytic lipase (10.65 ± 0.51 U/mL), and protease enzymes (13.28 ± 0.65 U/mL), which are responsible for the hydrolysis of the B. cinerea Str5 cell wall and, consequently, restrict fungal growth. The in vivo experiment on strawberry fruit showed that preen (uropygial) oil reduced the disease severity by 87.25%, while the endophytic bacteria B. safensis B3 reduced it by 86.52%. This study reports the efficiency of individually applied bioagents in the control of phytopathogenic fungi for the first time and, consequently, encourages their application as a new and innovative strategy for prospective agricultural technology and food safety

Arbuscular mycorrhizal strategy for zinc mycoremediation and diminished translocation to shoots and grains in wheat

<div><p>Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremediation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called <i>Funneliformis geosporum</i> (Nicol. & Gerd.) Walker & Schüßler. Experiments were performed using <i>Triticum aestivum</i> L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg^-1) and inoculated with or without <i>F</i>. <i>geosporum</i>. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil. However, the level of minerals of shoots, roots, and grains was greatly influenced by Zn-treatment and by inoculation with <i>F</i>. <i>geosporum</i>. Treatment with Zn in the soil increased Cu and Zn concentrations in the root, shoot and grains, however, other minerals (P, S, K, Ca and Fe) concentration was decreased. Inoculation of wheat with AM fungi significantly reduced the accumulation of Zn and depressed its translocation in shoots and grains of wheat. In conclusion, inoculation with a native <i>F</i>. <i>geosporum-</i>improves yields of wheat under higher levels of Zn and is possible to be applied for the improvement of zinc contaminated soil.</p></div

The phytoextraction efficiency (%), metal uptake (g pot^-1), and bioaccumulation factor (BCF) of Zn of wheat subjected to zinc treatments.

<p>Data presented as the mean of three replicates followed by the standard deviation (Mean±SD).</p

pH values, electrical conductivity (EC dsm^-1), cations and anions contents (mg/100 g), heavy metal contents (Fe and Zn mg kg^-1), phosphorus contents (P; mg kg^-1), the percentage of organic matter (OM%) and soils texture of 5 sites of cultivated soils.

<p>pH values, electrical conductivity (EC dsm^-1), cations and anions contents (mg/100 g), heavy metal contents (Fe and Zn mg kg^-1), phosphorus contents (P; mg kg^-1), the percentage of organic matter (OM%) and soils texture of 5 sites of cultivated soils.</p

Arbuscular mycorrhizal strategy for zinc mycoremediation and diminished translocation to shoots and grains in wheat - Fig 2

<p><b>(A) Chlorophyll-a, (B) Chlorophyll-b, (C) Carotenoid pigment content as mg g</b>^<b>-1</b><b>FW of leaves of mycorrhized and non-mycorrhized wheat grown at different levels of treatments with zinc are an average of five replicates, the error bars represent the standard error for the means.</b> ANOVA was performed to assess differences between treatment groups, followed by Duncan's multiple-rank comparisons. Media with similar letters are not significantly different according to Duncan's multiple range comparisons.</p

Influence of mycorrhizal colonization on lipid peroxidation as MDA (mmole g^-1 FW).

<p><b>The data represented are an average of five replicates; the error bars represent a standard error for the means.</b> ANOVA was performed to assess differences between treatment groups, followed by Duncan's multiple-rank comparisons. Media with similar letters are not significantly different according to Duncan's multiple range comparisons.</p

Influence of different levels of Zn on the mycorrhizal colonization of wheat.

<p>F% Frequency of mycorrhizal root segments, M% intensity of mycorrhizal colonization in the root, A% arbuscular frequency in the roots. The data represented are an average of three replicates (mean ± SD) followed by one standard deviation.</p

Mineral content in shoots, roots, and grains of wheat grown under different levels of zinc.

<p>The data represented are an average of three replicates ± standard deviation.</p