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Background: This study addresses the critical issue of Fusarium wilt in tomatoes, caused by Fusarium oxysporum f. sp. lycopersici (FOL), a severe fungal pathogen responsible for global yield losses. Conventional control measures, such as resistant crop varieties and chemical fungicides, have limitations due to environmental concerns and the risk of pathogen resistance. As a sustainable alternative, this study aims to explore the biocontrol potential of the bacterial strain Sh-17, focusing on its lipopeptides (LPs) to effectively suppress FOL. Results: This study demonstrated the antifungal capability of the Sh-17 strain, obtained from a tomato field, against FOL. Through 16S rDNA gene sequence analysis and phenotypic evaluation, Sh-17 was identified as Bacillus subtilis Sh-17. During the disease control assay using in vitro petri dishes, Sh-17 showed promising plant growth-promoting and disease-control capabilities in seedlings when tomato seeds were inoculated with both Sh-17 and FOL. Subsequently, the lipopeptide extract derived from Sh-17 showed strong antifungal properties in a dose-dependent manner, with complete inhibition of FOL at a concentration of 3500 µg mL−1. Furthermore, it was observed that LPs decreased the amount of ergosterol, which affects the stability and general structure of the plasma membrane. The genomic DNA of Sh-17 was subjected to PCR screening, which revealed the presence of genes responsible for the biosynthesis of antifungal LPs. Furthermore, LC–MS analysis identified distinct LPs, such as surfactins, fengycin, iturins, bacilysin, and bacillomycin derivatives in the crude LPs extract of Sh-17. Moreover, microscopic analyses (fluorescent/TEM) demonstrated morphological abnormalities and even death of the hyphae and spores of the phytopathogen upon its interaction with LPs. Conclusions: B. subtilis Sh-17 exhibits strong antifungal properties against FOL and supports seedlings health by protecting them from pathogen infestation. The LPs produced by Sh-17 inhibit FOL growth in a dose-dependent manner by disrupting the pathogen's cellular structures and proved to be an effective biocontrol agent against Fusarium wilt in tomatoes. [ABSTRACT FROM AUTHOR] more...

Abstract. The plant growth regulator 6-benzylaminopurine (BAP) is an important component of plant nutrient medium with tendency to accelerate physiological, biochemical and molecular processes in woody plants such as olive. To date, limited knowledge is available on the role of BAP in mediating physiological, biochemical and genetic activities in olives under in vitro conditions. To cover this research gap, the current study was conducted with the objective of studying the role of BAP in regulating physiological traits (chlorophyll, CO2 assimilation), antioxidant enzymes (superoxide dismutase, catalase and peroxidase), metabolic contents (starch, sucrose and flavonoids) and gene expression (OeRbcl, OePOD10, OeSOD10, OeCAT7, OeSS4, OeSuSY7, OeF3GT and OeChlH) under varying concentrations (0, 0.5, 1.5 and 2.5 mg L−1) within the provided in vitro conditions. The explants obtained from different olive cultivars ('Leccino', 'Gemlik', 'Moraiolo', 'Arbosana') were cultured on olive medium (OM) provided with different BAP concentrations using a two-factorial design, and data were analysed statistically. All traits increased significantly under in vitro conditions due to increasing concentrations of BAP; however, this increase was more dramatic at 2.5 mg L−1 and the least dramatic at 0.5 mg L−1. Moreover, correlation, principal component analysis and heatmap cluster analysis confirmed significant changes in the paired association and expression of traits with changing BAP concentration and type of olive cultivars. Likewise, the expression of all genes varied due to changes in BAP concentration in all cultivars, corresponding to variations in physiological and biochemical traits. Moreover, the spectrographs generated via scanning electron microscopy further indicated the variations in the distribution of elements in olive leaf samples due to varying BAP concentrations. Although all cultivars showed a significant response to in vitro varying concentrations of BAP, the response of Arbosana was statistically more significant. In conclusion, the current study proved the dynamic impact of the varying BAP concentrations on regulating the physiological, biochemical, and molecular attributes of olive cultivars. [ABSTRACT FROM AUTHOR] more...

Ficus palmata is an important fig species that produces edible and nutritious fruit and possesses several therapeutic uses. This study reports an effective method for the micropropagation of F. palmata using nodal explants. In vitro shoots were cultured for 7 weeks onto MS medium fortified with different concentrations of cytokinins, light intensities, sucrose concentrations, and light/dark incubation treatments. Optimal axillary shoot proliferation (10.9 shoots per explant) was obtained on a medium containing 30 g/L sucrose and supplemented with 2 mg/L 6-benzylaminopurine (BAP) under 35 μmol/m2/s light intensity. Dark incubation limited the foliage growth but favored shoot elongation and rooting compared with light incubation. Elongated shoots, under dark conditions, were rooted (100%; 6.67 roots per explant) onto MS medium containing 1 mg/L indole-3-acetic acid (IAA) and 1.5 g/L activated charcoal. The micropropagated plantlets were acclimatized with a 95% survival rate. In this study, the genetic fidelity of micropropagated F. palmata clones along with their mother plant was tested using randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeats (ISSR), and start codon targeted (SCoT) molecular markers. The genetic similarity between the micropropagated plantlets and the mother plant of F. palmata was nearly 95.9%, assuring high uniformity and true-to-type regenerated plants. Using micropropagated F. palmata plantlets as a rootstock proved appropriate for the grafting F. carica 'Brown Turkey'. These findings contribute to the commercial propagation and production of the fig crop. [ABSTRACT FROM AUTHOR] more...

Soybean is an important oilseed crop worldwide; however, it has a high sensitivity to temperature variation, particularly at the vegetative stage to the pod-filling stage. Temperature change affects physiochemical and genetic traits regulating the soybean agronomic yield. In this regard, the current study aimed to comparatively evaluate the effects of varying regimes of day and night temperatures (T1 = 20°C/12°C, T2 = 25°C/17°C, T3 = 30°C/22°C, T4 = 35°C/27°C, and T5 = 40°C/32°C) on physiological (chlorophyll, photosynthesis, stomatal conductance, transpiration, and membrane damage) biochemical (proline and antioxidant enzymes), genetic (GmDNJ1, GmDREB1G;1, GmHSF-34, GmPYL21, GmPIF4b, GmPIP1;6, GmGBP1, GmHsp90A2, GmTIP2;6, and GmEF8), and agronomic traits (pods per plant, seeds per plant, pod weight per plant, and seed yield per plant) of soybean cultivars (Swat-84 and NARC-1). The experiment was performed in soil plant atmosphere research (SPAR) units using two factorial arrangements with cultivars as one factor and temperature treatments as another factor. A significant increase in physiological, biochemical, and agronomic traits with increased gene expression was observed in both soybean cultivars at T4 (35° C/27°C) as compared to below and above regimes of temperatures. Additionally, it was established by correlation, principal component analysis (PCA), and heatmap analysis that the nature of soybean cultivars and the type of temperature treatments have a significant impact on the paired association of agronomic and biochemical traits, which in turn affects agronomic productivity. Furthermore, at corresponding temperature regimes, the expression of the genes matched the expression of physiochemical traits. The current study has demonstrated through extensive physiochemical, genetic, and biochemical analyses that the ideal day and night temperature for soybeans is T4 (35°C/27°C), with a small variation having a significant impact on productivity from the vegetative stage to the grain-filling stage. [ABSTRACT FROM AUTHOR] more...

The aim of this study was to compare agro-phenological and technological traits in advanced durum wheat lines differing in responses to Hessian fly larval attacks. A field experiment was carried out during the 2014/2015 cropping season at the main research stations of Marchouch and Tassaoute in a randomized completed block design. Twenty-two durum wheat genotypes comprising twenty advanced lines from the INRA breeding program and two commercial varieties were used in this study. Agro-phenological and grain quality determinations were concerned with plant height, grain yield, days to heading, protein content, wet gluten content, gluten strength, and yellow pigment content. The analysis of variance revealed significant environment, genotype, and genotype-by-environment (G × E) effects for the majority of the measured traits. A high level of heritability was also observed for grain yield (94.9%), followed by gluten strength (90.7%), yellow pigment content (79.3%), wet gluten content (77.79%), plant height (71.5), and protein content (70.02%); moderate levels of heritability were recorded for days to heading (65.8%). The data for Hessian fly resistance in both the field and infested greenhouse demonstrated three distinct group of genotypes: "resistant" with 4 genotypes, "susceptible without field escape to Hessian fly attack" with 16 genotypes, and "susceptible with field escape to Hessian fly attack" with 2 genotypes. The ANOVA analysis indicated the existence of significant differences between groups of genotypes for grain yield, days to heading, protein content, yellow pigment content, and gluten strength at the Tassaoute station, while at the Marchouch site, the differences were significant only for plant height and gluten strength. Protein content and wet gluten content revealed highly significant positive correlations, indicating the possibility of effective selection of the two traits simultaneously. Biplot analysis indicated that the first two Principal Components (PCs) accounted for 56.04% and 56.34% of the relationships between the genotypes and all of the attributes at the Marchouch and Tassaoute sites, respectively. The results of principal component analysis and Cluster based on agro-phenological and grain quality traits categorized the genotypes into three separate groups for the Marchouch site and four groups for the Tassaoute site. Individuals within each group are characterized by well-defined precocity, productivity, and technological criteria. The different behaviors of the lines studied in the present work are of great interest and can be exploited in breeding programs in order to improve agro-phenological and technological traits in durum wheat. [ABSTRACT FROM AUTHOR] more...