Effect of Humic Acid on Soil Physical and Chemical Properties, Microbial Community Structure, and Metabolites of Decline Diseased Bayberry.
International journal of molecular sciences
In recent years, bayberry decline disease has caused significant damage to the bayberry industry. In order to evaluate whether humic acid can be used to effectively control the disease, this research examined the nutritional growth and fruit quality of bayberry, soil physical and chemical properties, soil microbial community structure, and metabolites. Results indicated that the application of humic acid not only improved the vigor and fruit quality of diseased trees, but also increased the diversity of microbial communities in the rhizosphere soil. A great increase was observed in the relative abundance of bacterial genus and ; fungal genus and . In contrast, a significant decrease was observed in the relative abundance of bacterial genus , , , fungal genus of and . Analysis of redundancies (RDA) for microbial communities and soil characteristics showed that the main four variables, including available nitrogen, phosphorus, potassium, and calcium, had a great effect on the composition of bacterial and fungal communities in bayberry rhizosphere soil at the genus level. The main four variables had a greater effect on bacterial communities than on fungal communities. In addition, ABC transporter, arginine and proline metabolism, galactose metabolism, and glutathione metabolism were significantly affected by humic acid, which changed the content of 81 metabolites including 58 significantly down-regulated metabolites such as isohexonic acid and carinitine, and 23 significantly up-regulated metabolites such as acidic acid, guaninosuccinate, lyxose, 2-monoolein, epicatechin, and pentonolactone. These metabolites also significantly correlated with rhizosphere soil microbiota at the phylum, order, and genus levels. In conclusion, the results demonstrated the role of humic acid on plant growth and fruit quality, as well as rhizosphere soil characteristics, microbiota, and secondary metabolites, which provides novel insights into the control of bayberry decline disease.
10.3390/ijms232314707
The Impact of Using Different Doses of Biomass Ash on Some Physical Properties of Podzolic Soil under the Cultivation of Winter Oilseed Rape.
International journal of environmental research and public health
This two-year study was focused on the effect of the application of different biomass ash doses on selected soil physical properties, i.e., soil moisture (SM), bulk density (BD), penetration resistance (PR), and soil stability in water measured by the content of readily dispersible clay (RDC), following control and mineral NPK fertilization in the cultivation of winter oilseed rape ( L. var. napus). A one-factor field experiment conducted on podzolic soil (control, NPK, 100, 200, 300, 400, 500 kg KO·ha) showed that the use of biomass combustion ash significantly improved soil moisture at all depths and variants, and especially at a depth of 30-35 cm in the 500 kg·ha variant, i.e., by 2.99% /, compared to NPK. In turn, the moisture content in the 30-35 cm layer increased by 3.19% / in all variants in both years compared to the control. In 2020 and 2021, bulk density in the 0-5 cm layer treated with a dose of 500 kg·ha exhibited a positive 0.15 and 0.12 Mg·m decrease, respectively, compared to the control. In both years, the BD values in the 30-35 cm layer were reduced by 0.14 and 0.16 Mg·m compared to the control. The PR values decreased in the treatments with doses of 300, 400, and 500 kg·ha, especially in 2021. The RDC content was found to decline in both years, i.e., 2020 and 2021, upon the application of even the lowest dose (100 kg·ha) in all the analysed layers. The reduction in the RDC content, especially in the 0-5 cm layer, is very important for soil structure stability and to protect the soil environment. This layer is most susceptible to crusting, which results in poor aeration and weak plant emergence during drought and/or periods of excessive moisture. It may also increase surface runoff and intensify soil erosion processes.
10.3390/ijerph19116693
Black (air-cured) and blond (flue-cured) tobacco cancer risk. IV: Molecular dosimetry studies implicate aromatic amines as bladder carcinogens.
European journal of cancer (Oxford, England : 1990)
Tobacco smoking causes a major fraction of male urinary bladder cancers and the relative risk of bladder cancer is reported to be two to three times higher for smoking of black (air-cured) than for smoking of blond (flue-cured) tobacco. In molecular dosimetry studies to examine the hypothesis that aromatic amines in tobacco smoke are primarily responsible for bladder cancer, the higher bladder cancer risk in smokers of black tobacco was correlated with two to five times higher exposure to carcinogenic aromatic amines present in black tobacco smoke, notably 4-aminobiphenyl (ABP). For the same amount of smoking, black tobacco smokers had levels of ABP-haemoglobin (Hb) adducts 1.5 times higher and excreted a 1.8-fold higher level of urinary mutagens. These mutagens were characterised as aromatic amines, and included the heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a known mutagen and multiorgan/species carcinogen. In smoking volunteers, the ABP-Hb adduct level depended significantly on the acetylator and P-450IA2 phenotypes, being 1.3- to 1.5-fold lower in fast acetylators, slow/intermediate P-450IA2 individuals. The N-(deoxyguanosine-8-yl)-ABP adduct was a major smoking-related DNA adduct in bladder biopsies from surgical patients. It was also tentatively identified in exfoliated urothelial cells of smoking volunteers, who showed a significant and linear correlation between adduct levels of ABP with Hb and with deoxyguanosine in urothelial DNA; both were related to number of cigarettes smoked per day. Levels of several smoking-related DNA adducts in urothelial cells were 2-20 times elevated in smokers. Similar convex dose-response relationships have been found between the number of cigarettes smoked and the relative risk for bladder cancer and between the levels of ABP-Hb adducts and markers of recent smoking. A possible explanation is that fast and slow acetylators have different susceptibility to aromatic amine carcinogens. Case-control studies have consistently revealed an excess of variable magnitude of slow acetylators in subgroups exposed occupationally to carcinogenic aromatic amines. Altogether, results from these studies reinforce the association between cigarette smoking, carcinogen-DNA adducts in urothelial cells, and implicate primary aromatic and possibly heterocyclic amines as bladder carcinogens.
10.1016/s0959-8049(05)80315-6
Black (air-cured) and blond (flue-cured) tobacco and cancer risk II: Pharynx and larynx cancer.
European journal of cancer (Oxford, England : 1990)
Two case-control studies have examined the relationship between black or blond tobacco smoking and the occurrence of pharynx or larynx cancer. The first study was carried out in several European countries. Tobacco smoking was found to be associated with higher risks for supraglottic and epilarynx cancer localisations than for pharynx, glottic and subglottic localisation. In all localisations, risk was twice as high again in users of black tobacco after adjusting for alcohol and for lifetime average daily dose of tobacco. The other study was carried out in Uruguay. After taking into account age, age at start of smoking, duration of smoking, years since stopping smoking and filter use, risks were found to be higher in black tobacco smokers than in blond tobacco smokers. All known studies which have been performed in countries where blond tobacco is generally smoked showed lower risks even when adjusted for alcohol. Use of black tobacco appears to be associated with higher risks of cancer of the pharynx and larynx than blond tobacco use.
10.1016/0959-8049(93)90192-i
Black (air-cured) and blond (flue-cured) tobacco and cancer risk. I: Bladder cancer.
European journal of cancer (Oxford, England : 1990)
Four case-control studies in different Latin countries have reported risks of bladder cancer 2-3 times higher for smokers of black (air-cured) than for smokers of blond (flue-cured) tobacco. This observation is interesting in the light of a higher concentration of arylamines in black tobacco. The relative risk dropped very rapidly after discontinuation of smoking, and there was also an effect of age at start, with higher risks associated with earlier onset of the habit. Overall, black tobacco seems to act both on early and late stages of bladder carcinogenesis.
10.1016/0277-5379(91)90038-f