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In the current study, we used high-performance liquid chromatography (HPLC) and gas chromatography–mass spectrometry (GC–MS) to investigate and analyze the methanolic extract of Salvia rosmarinus leaves. HPLC analysis showed that the extract revealed a diverse array of polyphenolic compounds, including apigenin, catechin, chlorogenic acid, cinnamic acid, caffeic acid, coumaric acid, daidzein, ellagic acid, ferulic acid, gallic acid, hesperetin, kaempferol, methyl gallate, naringenin, pyrocatechol, quercetin, rutin, syringic acid, and vanillin. Furthermore, three fungal isolates from symptomatic strawberry plants were obtained and identified as Botrytis cinerea (OR116486), Fusarium oxysporum (OR116505), and Rhizoctonia solani (OR116525). The extract’s antifungal activity was evaluated at concentrations of 0, 50, 150, 200, and 300 µg/mL. At 200 µg/mL, the extract showed growth inhibition percentages of 74.56, 58.19, and 56.67% for R. solani, F. oxysporum, and B. cinerea, respectively, while at 300 µg/mL, all the tested fungi were completely suppressed. The GC–MS analysis revealed that the major compounds of the methanolic extract identified based on their retention times and relative peak areas (%) included β-caryophyllene (12.06%), germacrene d (13.55%), caryophyllene oxide (3.13%), methyl palmitate (5.26%), hexadecanoic acid (4.9%), and methyl stearate (6.02%). These results show rosemary extract’s potential as a source of natural antifungal agents against plant photogenic fungi. As a result, it provides a safer alternative to the current protective approaches for plant disease management.

Yellowing, extreme leaf distortion, and mosaic are all symptoms of the Papaya ring spot virus (PRSV). The objective of this research is to evaluate the effects of cinnamon, clove, garlic, fennel, ginger and chamomile extracts and some chemical inducers such as calcium chloride, nitric acid, pectin, oxalic acid, potassium chloride, tannic acid, disodium phosphate, P- Amino butyric acid (BABA), indole butyric acid (IPA) and salicylic acid on PRSV disease development in cucumber plants. Treatment with inducers decreased the severity and titer of PRSV under greenhouse conditions. In this regard, the cinnamon extract showed the best outcomes. Under field conditions, similar findings were obtained. Chemical and biotic treatments followed by PRSV inoculation resulted in potentiated induction of POD gene. In conclusion, utilizing inducers could be useful in practice because it could provide an easy, environmentally friendly, and economically acceptable method of protecting cucumber plants from PRSV while also reducing pollution from agricultural chemicals. [ABSTRACT FROM AUTHOR]

BACKGROUND Systemic resistance stimulated by rhizosphere bacteria is an important strategy for the management of plant viruses. The efficacy of Bacillus subtilis subsp. subtilis was assessed for protection of cucumber and Arabidopsis against Cucumber mosaic virus (CMV). Moreover, transcriptomic analysis was carried out for A. thaliana colonized with B. subtilis subsp. subtilis and infected with CMV. RESULTS: Treatment with a cell suspension of Bacillus revealed a significant reduction of CMV severity in comparison to their control. All Arabidopsis mutants treated with B. subtilis showed a clear reduction in CMV accumulation. Disease severity data and virus concentration titer measurements correlated with gene up‐regulation in microarray and reverse transcription quantitative polymerase chain reaction (RT‐qPCR) experiments. Bacillus treatment increased Arabidopsis growth characteristics (fresh and dry weights and number of leaflets) under pot conditions. The molecular mechanisms by which Bacillus activated resistance to CMV were investigated. Using the microarray hybridization technique, we were able to determine the mechanism of resistance elicited by B. subtilis against CMV. The transcriptomic analysis confirmed the up‐regulation of more than 250 defense‐related genes in Arabidopsis expressing induced systemic resistance (ISR). RT‐qPCR results validated the overexpression of defense genes (YLS9 and PR1 in Arabidopsis and PR1 and LOX in cucumber), implying their important roles in the stimulated defense response. CONCLUSION: Through the study of microarray and RT‐qPCR analyses, it can be concluded that the overexpression of pathogenesis‐related genes was necessary to stimulate CMV defense in cucumber and Arabidopsis by B. subtilis subsp. subtilis. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study fabricated titanium dioxide nanostructures (TDNS) to control broad bean stain virus (BBSV) in faba bean plants. Protection of faba bean against BBSV was evaluated biologically with respect to virus severity, reduction in BBSV accumulation and expression of a pathogenesis‐related gene. RESULTS: The results indicate that faba bean plants treated with TDNS show a significant reduction in disease severity relative to untreated plants. The regulatory and defense gene involved in the salicylic acid signaling pathway was highly expressed in faba bean plants treated with TDNS compared with untreated plants. The structural features of TDNS, such as the small particle size and suitable shape, contributed to its high efficacy against BBSV. Growth of faba bean plants treated with TDNS was significantly enhanced relative to untreated plants. CONCULSION: TDNS is an important, eco‐friendly and safe strategy for controlling BBSV in faba bean and this study is the first report of this control strategy. © 2018 Society of Chemical Industry Number of plant diseases such as viruses their control by chemicals are few, ineffective and nonexistent. TiO2 nanostructures effectively control BBSV in faba bean plants. [ABSTRACT FROM AUTHOR]

' Candidatus Phytoplasma australasia' causes important damages to the Egyptian vegetable crop production. A prerequisite for controlling the different diseases it causes to eggplant, tomato and squash, is to trace its propagation pathways. To allow the differentiation of 'Ca. P. australasia' strains, a multilocus sequence analysis protocol was developed. Four conserved phytoplama genes namely tuf, secY, dnaK and dppA, were selected among the CDS of a 'Ca. P. aurantifolia' genome draft. The corresponding genes were PCR amplified from tomato, eggplant and squash collected in 2010 from the governorates Sharkia, Elmynia and Beni sueif, as well as from Catharanthus roseus periwinkles collected in 2013 from Kafrelsheikh governorate. Sequence comparisons showed no diversity among the Egyptian isolates of 'Ca. P. australasia' that also constitute a distinct cluster within the 16SrII-D taxonomic subgroup. This low diversity supports a common epidemiology for the different diseases affecting vegetable crops and periwinkle in Egypt and suggests that future investigations on insect vector should focus on polyphagous leafhoppers. [ABSTRACT FROM AUTHOR]