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Early blight (EB), caused by Alternaria solani, is a serious problem in tomato production. Plant growth-promoting rhizobacteria promote plant growth and inhibit plant disease. The present study explored the bio-efficacy of synergistic effect of rhizobacterial isolates and ginger powder extract (GPE) against tomato EB disease, singly and in combination. Six fungal isolates from symptomatic tomato plants were identified as A. solani on the basis of morphological features i.e., horizontal septation (6.96 to 7.93 µm), vertical septation (1.50 to 2.22 µm), conidia length (174.2 to 187.6 µm), conidial width (14.09 to 16.52 µm), beak length (93.06 to 102.26 µm), and sporulation. Five of the twenty-three bacterial isolates recovered from tomato rhizosphere soil were nonpathogenic to tomato seedlings and were compatible with each other and with GPE. Out of five isolates tested individually, three isolates (St-149D, Hyd-13Z, and Gb-T23) showed maximum inhibition (56.3%, 48.3%, and 42.0% respectively) against mycelial growth of A. solani. Among combinations, St-149D + GPE had the highest mycelial growth inhibition (76.9%) over the untreated control. Bacterial strains molecularly characterized as Pseudomonas putida, Bacillus subtilis, and Bacillus cereus and were further tested in pot trials through seed bacterization for disease control. Seeds treated with bacterial consortia + GPE had the highest disease suppression percentage (78.1%), followed by St-149D + GPE (72.2%) and Hyd-13Z + GPE (67.5%). Maximum seed germination was obtained in the bacterial consortia + GPE (95.0 ± 2.04) followed by St-149D + GPE (92.5 ± 1.44) and Hyd-13Z + GPE (90.0 ± 2.04) over control (73.8 ± 2.39) and chemical control as standard treatment (90.0 ± 2). Ginger powder extracts also induce the activation of defence-related enzymes (TPC, PO, PPO, PAL, and CAT) activity in tomato plants. These were highly significant in the testing bacterial inoculants against A. solani infection in tomato crops. [ABSTRACT FROM AUTHOR]

Early blight disease causes a significant loss in tomato production. This study focuses on the effective suppression of Alternaria solani , which causes huge losses in tomato yield. This research was conducted at the Egyptian Atomic Energy Authority Nuclear Research Centre. Infected plants were treated with silver nanoparticles (AgNPs). Two chemical materials, sodium borohydride and trisodium phosphate, were used for the synthesized silver nanoparticles. 1% polyvinylpyridine (PVP) was used as a stabilizer agent. AgNPs were exposed to several doses of gamma irradiation (0, 1.5, 3, 6, 12, and 24) kilo Gray (kGy) in order to enhance and maximize the effect of AgNPs on Alternaria solani. UV–Vis spectroscopy (UV), Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM) were used to characterize AgNPs; sodium borohydride and trisodium citrate were used for the chemical reduction. AgNPs and AgNPs + gamma irradiation led to increases in shoot fresh weight and shoot dry weight; they also elevated the antioxidant enzymes, as well as peroxides and catalase, when compared with control (untreated) plants. AgNPs and AgNPs + gamma irradiation decreased the disease severity compared with the control untreated. Our study not only corroborates established trends in nano-agriculture but also introduces novel insights into the specific effects of gamma irradiation on AgNP that led to a decrease in this size in the quantum dot range (3–10) nm, as shown in Tem. By drawing parallels with the work of esteemed researchers in the field. • " Chemical Synthesis of AgNPs:Using Chemical Reduction of Synthesis AgNPs. • " Innovative Synthesis : Quantum Dote : Transforming AgNPs to quantum dot dimensions with the power of gamma irradiation." • " Thorough Characterization : Delving deep into the unique properties of irradiated AgNPs." • " Crop Guardian : Managing Early Blight Disease in tomatoes through the application of irradiated AgNPs." • " Plant Defense Boost : Irradiated AgNPs sparks heightened peroxidase and catalase activity, enhancing plant resilience." [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.), is an important horticulture crop supporting rural economy of Sirmaur district of Himachal Pradesh. Tomato crops in this geographical region are highly susceptible to plant pathogens resulting in significant loss of productivity and yield. In this study, we have determined the prevalence and causative pathogens of early blight disease affecting tomato crops in 18 geographical sites of district Sirmaur. On the basis of colony characteristics, microscopic features and ITS region sequence-based phylogenetic analysis, blight disease-associated isolates exhibited close resemblance to Alternaria alternata and other related species. These findings necessitates an integrated management strategy for effective pathogen control towards minimising the crop losses. [ABSTRACT FROM AUTHOR]

Three different fungitoxicants, i.e., Trichoderma harzianum, Bacillus subtilis and Roxil Plus WP50 fungicide, were investigated against tomato early blight disease caused by Alternaria solani fungus in vitro and in vivo. By using dual culture technique, the highest reduction percentage of A. solani growth was recorded with B. subtilis followed by Roxil treatments, while Roxil followed by T. harzianum treatments recorded highest reduction percentage of sporulation. Meanwhile, by using poisoned food technique the highest reduction percentage of A. solani growth was recorded with Roxil followed by B. subtilis treatments, while B. subtilis recorded highest reduction percentage of sporulation. Three fungitoxicants were investigated as foliar spray for their abilities for controlling early blight disease on naturally infected tomato plants under open field conditions. Roxil fungicide followed by B. subtilis treatments caused the highest significant reduction in disease incidence and disease severity percentage during the two successive growing seasons 2013/14 and 2014/15. Concerning to yield parameters, Roxil and T. harzianum treatments were significantly increased total yield weight and average weight of tomato fruit. Moreover, all tested treatments increased clearly total phenol content, peroxidase, polyphenoloxidase and chitinase activities, as well as, vitamince C contents as compared to control treatment. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) is among the most important vegetable crops worldwide. Early blight disease, caused by Alternaria solani, is a destructive foliar disease of tomato and other Solanaceae species. Herein, we investigated the in vitro antifungal properties of gallic acid and two of its derivatives (syringic and pyrogallic acids) against A. solani during 2019 and 2020 seasons. The physiological and biochemical effects of these compounds on infected tomato plants were also investigated using the whole plant bioassay. The in vitro investigation showed that all tested compounds showed fungistatic action and inhibited the mycelial radial growth of A. solani in a dose-dependent manner. In two separate pot-experiments, those compounds efficiently suppressed the development of the disease symptoms and area under disease progress curve (AUDPC), without any phytotoxic effects on the treated tomato plants. Additionally, all tested compounds positively enhanced the biochemical traits of treated plants including the chlorophyll content, the total soluble phenolics, the total soluble flavonoids, and the enzymatic activities of catalase, peroxidase, and polyphenol oxidase during 2019 and 2020 seasons. Moreover, the treatment with gallic acid and its derivatives significantly increased all yield components of A. solani-infected tomato plants such as the total number of flowers and fruits, and the fruit yield for each tomato plant in both experiments. Considering the fungitoxicity of phenolic acids against A. solani with no phytotoxicity on treated tomato plants, we believe that gallic acid and its derivatives might be a sustainable eco-friendly control strategy to reduce the usage of chemical fungicides partially or entirely against A. solani particularly, and fungal diseases in general. [ABSTRACT FROM AUTHOR]