Induction of Systemic Resistance in Tomato Plants Against Tomato yellow leaf curl virus in Protected Cultivation Using a Local Bacterial Isolate of Bacillus subtilis

Ghanem, H.M., E.H. Akel, Q.A. Al-Rhayeh and I.D. Ismail. 2021. Induction of Systemic Resistance in Tomato Plants Against Tomato yellow leaf curl virus in Protected Cultivation Using a Local Bacterial Isolate of Bacillus subtilis. Arab Journal of Plant Protection, 39(4): 289-295. https://doi.org/10.22268/AJPP-039.4.289295 This study was conducted at the Agricultural Scientific Research Center in Lattakia Governorate in a plastic house during the 2020/2021 growing season to evaluate the efficiency of the native bacterial isolate B.Ra.217 of Bacillus subtilis, in reducing infection of tomato plants with Tomato yellow leaf curl virus (TYLCV), by treating tomato seeds and later watering the seedlings with a suspension of the tested bacteria at a concentration of 1x109 /ml, and then measuring incidence (%) and severity of virus infection, and estimating peroxidase enzyme activity. The results showed that 30 days after inoculation with tomato leaf curl virus, a decrease in virus infection rate and severity in virus-infected and bacteria-treated plants compared with virus-infected and untreated control plants was observed. The reduction in disease incidence and severity of infection reached 26.67% and 34.28%, respectively, with significant differences between the treatments. In addition, the activity of peroxidase enzyme 7 days after infection with the virus showed an increase in plants treated with bacteria only (0.1342 μmol/mg) and those treated with bacteria and virus-infected (0.0913 μmol/mg), compared with the healthy control plants (0.0958 μmol/mg), and virus-infected and untreated with bacteria (0.0570 µmol/mg). The results also showed 15 days after infection that the enzyme activity was higher in plants treated with bacteria only (0.1592 µmol/mg) compared with the healthy control (0.1415 µmol/mg) with significant differences, and also the differences were significant with the untreated infected plants (0.1002 µmol/mg), and with inoculated and treated plants (0.1372 µmol/mg). Thus, this bacterial isolate may have an important applied role in enhancing tomato plant resistance to the virus and consequently reducing its damage. Keywords: Bacillus subtilis B.Ra.217, TYLCV, peroxidase, incidence, severity of infestation, tomato plant

The research of seed reproduction peculiarities of wild-growing Paeonia L. genus and perspectives of using peony seeds in food-processing industry

Vegetable oil is essential in everyday life of people. Lately, peonies are being widely used in food-processing industry of China – the seeds are processed for oil which is actively used as a food product, containing more than 90% unsaturated fatty acids. The problem of healthy eating is becoming more and more urgent. The task of Russian Federation science and all branches of AIC (agro-industrial complex) is to satisfy the physiological requirements of population in high-quality, biologically complete and safe food products. Production of peony oil in Russia would be of great importance for the economy of our country, as it is ecologically pure and safe food product for human health. In the article we researched the peculiarities of seed propagation and possible reasons for seed dormancy in some Paeonia L. genus. We carried out some bio-chemical tests in order to define the content of peroxidase enzyme, lignin and cellulose in seed peel. We also examined the intensity of photosynthesis and transpiration in 5 species of Paeonia L. genus: P. tenuifolia L., P. suffruticosa Andrews, P. lactiflora Pall., P. anomala L., P. mlokosewitschii Lomak. It was defined that the highest photosynthesis intensity can be observed in P. tenuifolia L. (86.1 mg/dm2h). Then P. mlokosevitschii Lomak. (65.1 mg/dm2h), P. suffruticosa Andrews. (59.3 mg/dm2h), P. anomala L. (32.8 mg/dm2h), P. lactiflora Pall. (2.15 mg/dm2h) follow. The examined species of Paeonia L. genus have high indices of photosynthesis intensity, and are able to adapt to changes in environment. The photosynthesis intensity is known to be one of the most important indices of high seed productivity and yielding capacity. We recommend using peony seeds in food industry for production of quality peony oil.

STUDY OF PHYSICOCHEMICAL PROPERTIES OF CAPSICUM POWDER BY DIFFERENT DRYING TECHNIQUES

The objective of this study was to analyse the effects of phytochemical parameter, physical parameter, color, and sensory analysis in green capsicum by different drying processes (microwave, freeze, and hot air drying). Results showed an increase in microwave output power (600W), decreased drying time, moisture content, Chroma, and bulk density values. The Freeze drying process significantly improved the lightness of dried capsicum. Due to take less time for the Microwave drying technique, phytochemical parameters are intact in capsicum; on the other side, color degradation has been occurred due to the Maillard reaction (L*=29.34±0.08, a*=6.98±0.09,b*=15.36±0.10). Bulk density (0.335±0.01) and dispersibility (40±2.00%) were highest in Microwave drying powder. The capsaicin content of dried capsicum was higher than the fresh capsicum sample, but compared to the different drying techniques, the Microwave drying sample has higher capsaicin content than the Hot air drying and Freeze-drying samples. The lower capsaicin content in fresh capsicum may occur due to the catalytic activity of the peroxidase enzyme. The capsaicin content of all dried capsicum varied between 1.91±0.05 and 3.31±0.16 mg/100 g. In this research, the Microwave drying powder of capsicum was the best product for its highest antioxidant content and other physical properties.

Effects of active molecules of Korean pine seed on rodent health and implications for forest regeneration

After maturation, Korean pine (Pinus koraiensis Siebold & Zucc.) seeds often cannot disperse to reach a suitable germination site. It is therefore difficult to naturally regenerate by itself and relies on animal dispersal. Squirrels hoard pine seeds as winter food and Korean pine seeds stored for overwintering might become the source of regeneration of the species. From field observations, the pine seeds are the food preference for squirrels during autumn in the Lesser Khingan Mountains in Northeast China. Such preference by squirrels has been attributed to high seed energy content and the ease of seed storage. However, it may also be expected from nutritional aspects that a coevolutionary relationship between squirrels and Korean pine species could be partially explained by the effect of active seed components and their physiological regulatory effects on squirrels. To test this hypothesis, control experiments were carried out to examine the modulatory effects of Korean pine nut oil (PNO) on intestinal microbiota, inflammatory profile and oxidative stress in mice. The results showed that, compared with mice fed a high-fat diet, PNO significantly improved the physical and the healthy state of mice. Histological analysis of the liver and epididymal fat tissue showed that PNO alleviated liver and adipocyte lesions, and inflammation caused by high-fat diets. PNO also significantly decreased atherosclerotic index and ameliorate serum lipid accumulation to prevent cardiovascular disease, which effect the positive control SG group. Moreover, PNO elevated superoxide dismutase and glutathione peroxidase enzyme activities and reduced malondialdehyde levels in the serum. 16S rRNA sequencing showed that PNO restored intestinal microbiota composition, significantly increasing the relative abundance of Lactobacillus and Akkermansia bacteria. These results suggest that Korean pine seeds not only provide adequate fat, protein and energy for squirrels, but also promote physical health and improve body immunity.

Peroxidase-like activity of Fe3O4/carbon core-shell nanostructured : effects of carbon shell thickness for application to glucose biosensor

In this study, we present a protocol for synthesis of carbon coated Fe3O4 nanoparticles with core-shell structured nanocomposite (FeC) following a two steps approach. The peroxidase-like acitivity of the synthesized FeC nanocomposite has been evaluated towards replacing of the horseradish peroxidase enzyme (HRP) in hydrogen peroxide enzymatic biosensor. In which, FeC has catalyzed for a redox reaction 5,5'-tetramethylbenzidine (TMB) and H2O2 to produce oxidized state of TMB with as a blue color. Results exhibited that FeC has a high catalytic activity accepting for fabrication of a high selectivity hydrogen peroxide (H2O2) colorimetric sensor with low detection of limit (LoD) of 0.02 mM H2O2. Based on this finding, we have used FeC and combined with glucose oxidase (GOx) enzyme to construct a new colorimetric glucose biosensor with high selectivity.

Comparative Study of Secreted Proteins, Enzymatic Activities of Wood Degradation and Stilbene Metabolization in Grapevine Botryosphaeria Dieback Fungi

Botryosphaeriaceae fungi are plant pathogens associated with Botryosphaeria dieback. To better understand the virulence factors of these fungi, we investigated the diversity of secreted proteins and extracellular enzyme activities involved in wood degradation and stilbene metabolization in Neofusicoccum parvum and Diplodia seriata, which are two major fungi associated with grapevine B. dieback. Regarding the analysis of proteins secreted by the two fungi, our study revealed that N. parvum, known to be more aggressive than D. seriata, was characterized by a higher quantity and diversity of secreted proteins, especially hydrolases and oxidoreductases that are likely involved in cell wall and lignin degradation. In addition, when fungi were grown with wood powder, the extracellular laccase and Mn peroxidase enzyme activities were significantly higher in D. seriata compared to N.parvum. Importantly, our work also showed that secreted Botryosphaeriaceae proteins produced after grapevine wood addition are able to rapidly metabolize the grapevine stilbenes. Overall, a higher diversity of resveratrol and piceatannol metabolization products was found with enzymes of N. parvum compared to D. seriata. This study emphasizes the diversity of secreted virulence factors found in B. dieback fungi and suggests that some resveratrol oligomers produced in grapevine wood after pathogen attack could be formed via pathogenic fungal oxidases.