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Cercospora leaf spot caused by Cercospora beticola are among the most dangerous plant diseases on sugar beet plants. It causes heavy economic losses, whether on the yield of roots, the percentage of sugar in them, or the quality of sugar produced. In addition to the economic cost caused by chemical control, these chemical pesticides cause an imbalance in the ecosystem and harm the health of humans and animals. In an attempt to search for a safer method than pesticides and environmentally friendly, an evaluation of using biocontrol agents, Bacillus subtilis as cell suspension (108 cell/ml), was conducted in this study. Seeds extract of Moringa oleifera with two concentrations (25 and 50 g/L) and potassium bicarbonate at (5 and10 g/L (compared to fungicide Montoro 30% EC (Propiconazole 15% + Difenoconazole 15%). The evaluation results for twenty-five sugar beet varieties showed a significant discrepancy between these varieties in the extent of their susceptibility to infection with the disease under investigation. In-Vitro , B. subtilis induced an antagonist to C. beticola , and both M. oleifera seeds extract and potassium bicarbonate significantly reduced the linear growth of this pathogen. Under field conditions, the treatments used have given positive results in controlling Cercospora leaf spots. They significantly decreased the severity of disease and prevented C. beticola from creating conidiophores and conidiospores, along with examining their cell walls with the formation of plasmolysis of the fungus cells and reducing both the number and diameter of the spots on the surface leaves; this was demonstrated using a scanning electron microscope (SEM). It is worth noting that the best results obtained were most often when treated with M. oleifera seeds extract, followed by potassium bicarbonate, then cell suspension of B. subtilis. In addition, the percentage of the content of beet roots from total soluble solids and sucrose has improved significantly due to spraying sugar beet plants with the substances mentioned earlier. These treatments also contributed to a significant improvement in the enzymes polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase. [ABSTRACT FROM AUTHOR]

The excessive accumulation of hexavalent chromium (Cr(VI)) in the environment poses a risk to environment and human health. In the present study, a potassium bicarbonate-modified pyrite/porous biochar composite (PKBC) was prepared in a one-step process and applied for the efficient removal of Cr(VI) in wastewater. The results showed that PKBC can significantly remove Cr(VI) within 4 h over a wide range of pH (2–11). Meanwhile, the PKBC demonstrated remarkable resistance towards interference from complex ions. The addition of potassium bicarbonate increased the pore structure of the material and promoted the release of Fe2+. The reduction of Cr(VI) in aqueous solution was primarily attributed to the Fe(II)/Fe(III) redox cycle. The sulphur species achieved Fe(II)/Fe(III) cycle through electron transfer with iron, thus ensuring the continuous reduction capacity of PKBC. Besides, the removal rate was also maintained at more than 85% in the actual water samples treatment process. This work provides a new way to remove hexavalent chromium from wastewater and demonstrates the potential critical role of potassium bicarbonate and sulphur. [Display omitted] • Cr(VI) removal by potassium bicarbonate-modified pyrite/porous biochar (PKBC) was improved. • Potassium bicarbonate increased pore structure and promoted the release of Fe2+. • PKBC enabled Cr(VI) removal over a wide pH range. • PKBC implemented Cr(VI) reduction through Fe(II)/Fe(III) cycling. • Sulphur species achieved Fe(II)/Fe(III) cycle through electron transfer with iron. [ABSTRACT FROM AUTHOR]

Abstract: A total of nine biorational fungicides were examined during the 2000 and 2001 growing seasons for their ability to manage rusty spot epidemics, caused by Podosphaera leucotricha, on moderately susceptible ‘Jerseyglo’ peach. The biorationals studied were the biological control agents Bacillus subtilis, Ampelomyces quisqualis and Phoma glomerata; the plant extracts neem seed oil, cinnamon oil and extracts from leaves of giant knotweed, Reynoutria sachalinensis; the inorganic compounds potassium bicarbonate and potassium dihydrogen phosphate; and chitosan, a deacetylated form of chitin derived from crustacean shells. Disease assessments, consisting of fruit lesion counts, were made at three- to six-day intervals during the course of the epidemics. Three biorational fungicides, B. subtilis, neem seed oil extract and potassium bicarbonate, significantly reduced areas under the disease incidence and lesion density progression curves in both years of the study. The remaining biorational materials reduced disease in only one year or neither year. When the logistic model was fit to the disease progress curves, the three most effective biorationals also significantly reduced the estimated maximum disease level or carrying capacity parameter K. Although these reductions were statistically significant, the amount of disease control was relatively low, ranging from 24 to 34%, versus 94% control for the myclobutanil standard. Thus, B. subtilis, neem seed oil extract and potassium bicarbonate provide insufficient efficacy for commercial management of rusty spot when applied alone. However, since these biorationals consistently provided some levels of control, they may be candidates for use in integrated programs with conventional fungicides. [Copyright &y& Elsevier]

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Experimental results in the past years recommend using potassium bicarbonate like fungicide in preventing and control apple scab and other apple diseases. Experimental field was carried out in 2010 at a commercial orchard of SC Agroindustriala SA Cluj-Napoca, Romania. The trees were planted in 2003 at a distance of 3.5 x 0.9 m. The efficacy of potassium bicarbonate, potassium phosphate, potassium silicate and mixture between these in comparison with other cupper and sulphur based fungicides in preventing and control apple scab on four apple cultivars ('Golden Delicious', 'Starkrimson', 'Jonathan', 'Idared') was tested. Potassium bicarbonate, potassium phosphate, potassium silicate and mixture between these proved to be more effective in reducing attack of apple scab on leaves and fruit of the apple cultivars studied like wettable sulphure (4 kg/ha) or copper hydroxide (5 kg/ha). Results were obtained in a year with favourable conditions of scab infection and development, when untreated variants control had an attack degree (AD%) ranged 18.0- 50.2 %. Potassium bicarbonate, potassium phosphate, potassium silicate and mixture between these assures the best results at 'Idared' and 'Jonathan' cultivars, where the attack degree was reduced by about three times. The treatments with the products used in experiments not registered symptoms of phytotoxicity on leaves or flowers. Given that this product is not toxic to human health, it becomes a perspective fungicide especially for organic fruit tree growing to control apple scab. [ABSTRACT FROM AUTHOR]

To determine the effects of potassium supplementation on endothelial function, cardiovascular risk factors, and bone turnover and to compare potassium chloride with potassium bicarbonate, we carried out a 12-week randomized, double-blind, placebo-controlled crossover trial in 42 individuals with untreated mildly raised blood pressure. Urinary potassium was 77+/-16, 122+/-25, and 125+/-27 mmol/24 hours after 4 weeks on placebo, potassium chloride, and potassium bicarbonate, respectively. There were no significant differences in office blood pressure among the 3 treatment periods, and only 24-hour and daytime systolic blood pressures were slightly lower with potassium chloride. Compared with placebo, both potassium chloride and potassium bicarbonate significantly improved endothelial function as measured by brachial artery flow-mediated dilatation, increased arterial compliance as assessed by carotid-femoral pulse wave velocity, decreased left ventricular mass, and improved left ventricular diastolic function. There was no significant difference between the 2 potassium salts in these measurements. The study also showed that potassium chloride reduced 24-hour urinary albumin and albumin:creatinine ratio, and potassium bicarbonate decreased 24-hour urinary calcium, calcium:creatinine ratio, and plasma C-terminal cross-linking telopeptide of type 1 collagen significantly. These results demonstrated that an increase in potassium intake had beneficial effects on the cardiovascular system, and potassium bicarbonate may improve bone health. Importantly, these effects were found in individuals who already had a relatively low-salt and high-potassium intake. [ABSTRACT FROM AUTHOR]