Probing the interaction of Paenibacillus larvae bacteriophage as a biological agent to control the american foulbrood disease in honeybee.

American foulbrood (AFB) is a harmful honeybee disease primarily caused by Paenibacillus larvae. The study aims to isolate and identify the AFB causative agent P. larvae and their specific phages to use as a new biological method for AFB disease control. Eight apiaries were inspected for AFB infections. Symptoms of diseased brood comb, were odd brood cells with soft brown decayed brood amongst healthy brood, were identified in the field and demonstrated the prevalence of AFB in every apiary. Three P. larvae isolates were identified using traditional techniques using a 452-bp PCR amplicon specific to the bacterial 16SrRNA gene and was compared between Paenibacillus isolates. Additionally, specific phages of P. larvae strains were applied to examine their efficiency in reducing the infection rate under the apiary condition. The infection rate was reduced to approximately 94.6 to 100 % through the application of a phage mixture, as opposed to 20 to 85.7 % when each phage was administered individually or 78.6 to 88.9 % when antibiotic treatment was implemented. Histological studies on phage-treated bee larvae revealed some cells regaining normal shape, with prominent nuclei and microvilli. The gastrointestinal tract showed normal longitudinal and circular muscles, unlike bee larvae treated with bacterial strains with abnormal and destroyed tissues, as shown by the basement membrane surrounding the mid-gut epithelium. Phage techniques exhibited promise in resolving the issue of AFB in honeybees due to their ease of application, comparatively lower cost, and practicality for beekeepers in terms of laboratory preparation.

Biochar-enhanced anaerobic mixed culture for biodegradation of 1,2-dichloroethane: Microbial community, mechanisms, and techno-economics.

While anaerobic digestion (AD) has been employed for the degradation of chlorinated aliphatic hydrocarbons, the associated digester performance might suffer from volatile fatty acids accumulation, insufficient substrate-microbes interaction, and lower biogas yields. To overcome these limitations, this study is the first to augment the hydrocarbon-degrading microbial capacities by adding agricultural waste-based biochar to the digestion medium. 1,2-dichloroethane (1,2-DCA) was selected as the target pollutant because it is discharged in large quantities from oil refining, petrochemical, and chemical industries, causing serious environmental and human health concerns. A multi-chamber anaerobic reactor (MAR) was operated at a 1,2-DCA loading rate of 1.13 g/L/d, glucose dosage (as an electron donor) range of 200-700 mg/L, and hydraulic retention time of 11.2 h, giving dechlorination = 32.2 ± 6.9% and biogas yield = 210 ± 30 mL/g CODremoved. These values increased after biochar supplementation (100 mg/g volatile solids, VS, as an inoculum carrier) up to 60.2 ± 11.5% and 290 ± 40 mL/g CODremoved, respectively, owing to the enhancement of dehydrogenase enzyme activities. Burkholderiales (15.3%), Clostridiales (2.3%), Bacteroidales (3.5%), Xanthomonadales (3.3%), and Rhodobacterales (6.1%) involved in 1,2-DCA degradation were dominant in the reactor supplemented with biochar. It's suggested that biochar played a major role in facilitating the direct interspecies electron transfer (DIET) between syntrophic bacteria and methanogens, where chloride, ethylene glycol, and acetate derived from 1,2-DCA dechlorination could be further used to promote methanogenesis and methane production. The synergetic effect of adsorption and dechlorination towards 1,2-DCA removal was validated at various biochar dosages (50-120 mg/g) and 1,2-DCA concentrations (50-1000 mg/L). The techno-economic results showed that the cost of treating 1,2-DCA-laden discharge (100 m3/d) by the MAR module could be 0.83 USD/m3 with a payback period of 6.24 years (NPV = 2840 USD and IRR = 10%), retrieving profits from pollution reduction (9542 USD/yr), biogas selling (10418 USD/yr), and carbon credit (10294 USD/yr).

Common viral and bacterial avian respiratory infections: an updated review.

Many pathogens that cause chronic diseases in birds use the respiratory tract as a primary route of infection, and respiratory disorders are the main leading source of financial losses in the poultry business. Respiratory infections are a serious problem facing the poultry sector, causing severe economic losses. Avian influenza virus, Newcastle disease virus, infectious bronchitis virus, and avian pneumovirus are particularly serious viral respiratory pathogens. Mycoplasma gallisepticum, Staphylococcus, Bordetella avium, Pasteurella multocida, Riemerella anatipestifer, Chlamydophila psittaci, and Escherichia coli have been identified as the most serious bacterial respiratory pathogens in poultry. This review gives an updated summary, incorporating the latest data, about the evidence for the circulation of widespread, economically important poultry respiratory pathogens, with special reference to possible methods for the control and prevention of these pathogens.

Phylogenetic Diversity of Trichoderma Strains and Their Antagonistic Potential against Soil-Borne Pathogens under Stress Conditions.

Trichoderma species are known as excellent biocontrol agents against soil-borne pathogens that cause considerable crop losses. Eight strains of Trichoderma were isolated from five Egyptian regions. They identified based on translation elongation factor-1α (TEF1) sequencing as four different Trichoderma species: Trichoderma asperellum, Trichoderma harzianum, Trichoderma viride, and Trichoderma longibrachiatum. Optimal growth conditions (temperature and media), and the phosphate solubilization capability of Trichoderma strains were evaluated in vitro. Further, the ability of these strains to antagonize Fusarium solani, Macrophomina phaseolina, and Fusarium graminearum was also evaluated. The results revealed that Trichoderma harzianum (Th6) exhibited the highest antagonistic ability against F. solani, M. phaseolina and F. graminearum with inhibition rates of 71.42%, 72.97%, and 84.61%, respectively. Trichoderma viride (Tv8) exhibited the lowest antagonism against the same pathogens with inhibition rates of 50%, 64% and 69.23%, respectively. Simple-sequence repeats (SSRs) and random amplified polymorphic DNA (RAPD) markers were used to evaluate the genetic variability of the Trichoderma strains. The results revealed that of 45 RAPD amplified bands, 36 bands (80%) were polymorphic and of SSRs amplified 36 bands, 31 bands (86.11%) were polymorphic. The amplification of calmodulin and ß-1,3-endoglucanase was noted at 500 bp and 230 bp, respectively. Data indicated that T. viride (Tv8) had the highest phosphate solubilization index (10.0 mm), while T. harzianum (Th6) had the lowest phosphate solubilization index (4.0 mm). In conclusion, T. harzianum (Th6) had the highest antagonistic activity in dual culture assay along with the growth rate; while T. viride (Tv8) had the highest phosphate solubilization activity. There are still gaps in obtaining new formulations, selecting potent Trichoderma strains to confirm disease control in planta. For improving Trichoderma recommendation in the organic agricultural system and sustaining the fertility of the soil, the field application of highly antagonistic biocontrol agents in different types of soil and plant species will be the first approach toward bio-pesticide treatments along with bio-fertilizer inoculation. Furthermore, secondary metabolites will be investigated for the most promising strains with the combination of different pathogens and application timing.