Plant pathogens are the main threat for profitable agricultural productivity. Currently, chemicalbased pesticides are thought to be an effective and reliable agricultural management measure for controlling pests. Chemical pesticides are highly effective and convenient to use but they are a potential threat for the environment and all kinds of life on earth. Therefore, the use of biological control agents for the management of plant pathogens is considered as a safer and sustainable strategy for safe and profitable agricultural productivity. Bacillus-based biocontrol agents play a fundamental role in the field of biopesticides. Many Bacillus species have proved to be effective against a broad range of plant pathogens. They have been reported as plant growth promoter, systemic resistance inducer, and used for production of a broad range of antimicrobial compounds (lipopeptides, antibiotics and enzymes) and competitors for growth factors (space and nutrients) with other pathogenic microorganisms through colonization. The aim of this article is to present the biocontrol potential of Bacillus species in relation with their antagonizing attributes against plant pathogens. These attributes include production of lipopeptides, antibiotics and enzymes as well as plant growth promotion and systemic induced resistance.

plant extracts contain many active compounds, which are tremendously fruitful for plant defence against several insect pests. the prime objectives of the present study were to calculate the extraction yield and to evaluate the leaf extracts of Citrullus colocynthis (L.), Cannabis indica (L.) and Artemisia argyi (L.) against Brevicoryne brassicae and to conduct biochemical analysis by gas chromatography-mass spectrometry (Gc-MS). the results suggested that when using ethanol, C. colocynthis produced a high dry yield (12.45%), followed by that of C. indica and A. argyi, which were 12.37% and 10.95%, respectively. The toxicity results showed that A. argyi was toxic to B. brassicae with an Lc 50 of 3.91 mg mL −1 , followed by the toxicity of C. colocynthis and C. indica, exhibiting Lc 50 values of 6.26 and 10.04 mg mL −1 , respectively, which were obtained via a residual assay; with a contact assay, the Lc 50 values of C. colocynthis, C. indica and A. argyi were 0.22 mg mL −1 , 1.96 and 2.87 mg mL −1 , respectively. the interaction of plant extracts, concentration and time revealed that the maximum mortality based on a concentration of 20 mg L −1 was 55.50%, the time-based mortality was 55% at 72 h of exposure, and the treatment-based mortality was 44.13% for A. argyi via the residual assay. on the other hand, the maximum concentration-based mortality was 74.44% at 20 mg mL −1 , the time-based mortality was 66.38% after 72 h of exposure, and 57.30% treatment-based mortality was afforded by A. argyi via the contact assay. the biochemical analysis presented ten constituents in both the A. argyi and C. colocynthis extracts and twenty in that of C. indica, corresponding to 99.80%, 99.99% and 97% of the total extracts, respectively. Moreover, the detected caryophylleneonides (sesquiterpenes), α-bisabolol and dronabinol (Δ 9-tHc) from C. indica and erucylamide and octasiloxane hexamethyl from C. colocynthis exhibited insecticidal properties, which might be responsible for aphid mortality. However, A. argyi was evaluated for the first time against B. brassicae. It was concluded that all the plant extracts possessed significant insecticidal properties and could be introduced as botanical insecticides after field evaluations. The cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae), is a serious pest native to Europe but now found globally 1,2 , and it causes significant losses to economically important crops, including broccoli, oilseed rape, brussels sprouts, cauliflower, black and white mustard, toria, Chinese cabbage, kale, and other field crops 1. It also causes yellowing, stunting, and plant wilting and acts as a vector of several viral diseases in crucifers, including cauliflower mosaic virus and turnip mosaic virus 3,4. In the case of severe infestation, plants become covered with aphids, resulting in leaf surfaces roofed with black mould due to honey secretion, which can ultimately cause

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ANN and RSM based modelling for optimization of cell dry mass of Bacillus sp. strain B67 and its antifungal activity against Botrytis cinerea

Brevicoryne brassicae is a problematic pest in cabbage and other field crops. Synthetic pesticides are used to control this pest, but they are injurious for human health and the environment. The present study aimed to purify and identify the active compounds from Citrullus colocynthis leaves with an appraisal of their efficacy against B. brassicae. Separation and purification were performed via different chromatographic techniques. Molecular analysis and chemical structures were recognized by mass spectrum (MS) and nuclear magnetic resonance (NMR), respectively. Moreover, in vitro and in vivo aphicidal activity was assessed using various concentrations, i.e., 6.25, 12.5, 25 and 50 µg/mL at 12, 24, 48 and 72 h exposure. The outcome shows that mass spectrum analyses of the purified compounds suggested the molecular formulae are C30H50O and C29H50O, C29H48O. The compounds were characterized as fernenol and a mixture of spinasterol, 22,23-dihydrospinasterol by 1H-NMR and 13C-NMR spectrum analysis. The toxicity results showed that the mixture of spinasterol and 22,23-dihydrospinasterol showed LC50 values of 32.36, 44.49 and 37.50 µg/mL by contact, residual and greenhouse assay at 72 h exposure, respectively. In contrast, fernenol recorded LC50 values as 47.99, 57.46 and 58.67 µg/mL, respectively. On the other hand, spinasterol, 22,23-dihydrospinasterol showed the highest mortality, i.e., 66.67%, 53.33% and 60% while, 30%, 23.33% and 25% mortality was recorded by fernenol after 72 h at 50 µg/mL by contact, residual and greenhouse assay, respectively. This study suggests that spinasterol, 22,23-dihydrospinasterol are more effective against B. brassicae which may be introduced as an effective and suitable substitute of synthetic chemical pesticides.

One new indole derivative, chloroindole (1), one new diketone, streptoone A (2), two new ketonic acids, streptoones B (3) and C (4), and one known macrolide antibiotic, X-14952B (5), were isolated from Streptomyces sp. SN0280. Extensive NMR, HRESIMS, and IR analysis was used to elucidate their structures. Streptoone A (2) displayed antibacterial activity (MIC value of 7.81 μg/mL) against Clavibater michiganensis, comparable with the positive control streptomycin (MIC value of 7.81 μg/mL). Streptoone B (3) showed antifungal activity (MIC value of 15.63 μg/mL) against Phytophthora capsici (positive control carbendazol MIC value of 7.81 μg/mL). These molecules provide new templates for the potential treatment and management of these phytopathogens.

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Sagittaria trifolia is a medicinal foodstuff of China and East Asia belonging to the family Alismataceae. Samples of S. trifolia tubers were collected from Meihekow, Siping, Jilin, Harbin and Wuchang from Northeast China. The current study was aimed to evaluate the qualitative and quantitative analysis, antioxidant activity, biochemical analysis and chemical composition of different populations of S. trifolia. By using Folin–Ciocalteu, aluminium chloride colourimetric and 1,1-diphenyl-1-picrylhydrazyl (DPPH), total phenol and flavonoids content and antioxidant activity was analysed. Furthermore, chemical composition, biochemical analysis and mineral substances were also determined. The results showed the presence of flavonoids, phenols, saponins, tannins, glycosides and steroids except for alkaloids and terpenoids by qualitative analysis. Quantitative analysis revealed that highest total phenol, flavonoids content and antioxidant potential identified from Meihekow, i.e., 2.307 mg GAE/g, 12.263 mg QE/g and 77.373%, respectively. Gas chromatography-mass spectrometry results showed the presence of 40 chemical compounds corresponding to 99.44% of total extract that might be responsible for antioxidant properties. Mineral and biochemical analysis revealed the presence of calcium, magnesium, potassium, sodium, iron, copper, zinc and, carbohydrate, protein, fibre and fat contents, respectively. Interestingly, all S. trifolia populations collected from different locations possess similar composition. The dietary values, phytoconstituents, antioxidant activities and nutritional and curative chemical compounds of S. trifolia are beneficial for the nutritherapy of human beings.