Effect of Liquid Organic Fertilizers and Soil Moisture Status on Some Biological and Physical Properties of Soil

This study was conducted to evaluate the effects of liquid organic fertilizers (LOFs) and soil moisture status on some biological and physical properties of postharvest soil of maize cultivation. For this purpose, a factorial greenhouse experiment was performed based on the completely randomized design with three replications. Treatments consisted of five levels of LOFs (control, vermicompost tea, vermiwash, plant growth-promoting rhizobacteria [PGPR] enriched vermicompost tea and PGPR enriched vermiwash) and three levels of soil moisture status (field capacity [FC], 0.8 FC and 0.6 FC). The results showed LOFs caused an increase of soil biological properties (soil microbial respiration, soil microbial biomass, dehydrogenase activity and the number of aerobic heterotrophic bacteria) and the improvement of soil physical condition. LOFs increased aggregate stability, hydrophobicity and total porosity, while decreased bulk density and soil penetration resistance. Increasing water stress levels reduced soil biological activity and made soil physical properties more unfavorable. In general, LOFs improved soil conditions by enhancing soil physical and biological properties and decreased the negative effects of water stress. In addition, results showed that LOFs enriched with PGPR could be more effective than non-enriched ones

Influence of arbuscular mycorrhiza fungi, rice-husk-drived biochar and compost on dry matter yield, nutrients uptake and secondary metabolites responses of Iranian borage Echium amoenum Fisch & C. A. Mey

In einem Gewächshausversuch wurde der Einfluss von Bio-Düngern wie vesikulär-arbuskulärer Mykorrhiza, Biochar aus Reisspreu und Biokompost auf Ertrag, Nährstoffaufnahme und sekundäre Inhaltstoffe der Medizinalpflanze Echium amoneum; Fisch & C. A. Mey (iranisches Gurkenkraut) geprüft. Die Varianten waren komplett randomisiert. Alle Behandlungen zeigten signifikante Effekte auf Trockenmasse, Nährstoffaufnahme und Gehalte an Chlorophyll, Carotinoiden, Prolin, Anthocyanen, Flavonoiden, Schleimstoffen und Kohlenhydraten.This study was carried out to investigate the effect of bio-fertilizers including mycorrhiza (MY), rice husk compost (RHC), and biochar (RHB) on dry matter yield, nutrients uptake and some secondary metabolites of the medicinal plant Echium amoenum Fisch & C. A. Mey. The experiment was conducted in a completely randomized design and executed with six treatments and six replications. Treatments comprised of T1: control, T2: MY, T3: RHC, T4: RHB, T5: RHC+MY and T6: RHB+MY. The following parameters were studied: leaf dry weight, macro and micro nutrient uptake, chlorophyll a, chlorophyll b, carotenoids, proline, anthocyanin, flavonoid, mucilage and carbohydrate content. The results show that application of RHC, RHB and MY individually or in combination significantly affected the studied parameters in comparison with the control treatment. In all cases, combined appli­cation of bio-fertilizers together with mycorrhiza application (T5 and T6) had a more positive impact on the studied parameters compared to the application of each treatment alone

The effect of arbuscular mycorrhiza, rice husk compost and biochar on Iranian borage Echium amoenum Fisch & C. A. Mey and post-harvesting soil properties

In einem Gewächshausversuch wurde der Einfluss von Bio-Düngern, wie vesikulär-arbuskulärer Mykorrhiza, Compost und Biochar aus Azolla-Algen auf Ertrag, Ertragsstruktur sowie die Aufnahme an Haupt- und Spurenelementen von iranischem Gurkenkraut geprüft. Gegenstand der Untersuchung war auch der Nährstoffgehalt der Böden nach der Ernte, sowie deren biologische Aktivität. Alle geprüften Behandlungen zeigten im Vergleich zu den Kontrollen signifikante Effekte auf Ertrag und Nährstoffaufnahme. Höhere Bodenatmung und eine höhere mikrobielle Biomasse indizieren eine Steigerung der Fruchtbarkeit der Böden durch die Behandlungen. DOI: 10.5073/JfK.2019.01.02, https://doi.org/10.5073/JfK.2019.01.02This study was conducted to investigate the effect of rice husk compost (RHC), rice husk biochar (RHB) and mycorrhization (MY) on some properties of Iranian Echium amoenum Fisch & C. A. Mey and also on some selected post-harvesting soil properties. A completely randomized design experiment was conducted with six treatments and six replications. Treatments comprised T1: control, T2: MY, T3: RHC, T4: RHB, T5: RHC + MY and T6: RHB + MY. Studied parameters included; shoot and root fresh weights, root and leaf length, shrub height, leaf number, shoot and root NPK content, shoot and root Fe, Zn, Cu and Mn concentration, root colonization percentage, soil NPK status, soil micronutrients concentrations, soil respiration and microbial biomass. Results revealed that application of RHC, RHB and MY individually or in combination with other treatments significantly affected studied parameters. In all cases except for root colonization, combined application (T5 and T6) had more satisfied impacts compared with a single application of treatments. DOI: 10.5073/JfK.2019.01.02, https://doi.org/10.5073/JfK.2019.01.0

Impacts of PGPR, compost and biochar of Azolla on dry matter yield, nutrient uptake, physiological parameters and essential oil of Rosmarinus officinalis L.

In einem Gewächshausversuch wurde der Einfluss von Bio-Düngern wie PGPR, Compost und Biochar aus Azolla-Algen auf Ertrag, Nährstoffaufnahme und diverse Inhaltstoffe der Gewürzpflanze Rosmarin geprüft. Alle Behandlungen zeigten im Vergleich zu den Kontrollen sig­nifikante Effekte auf Ertrag, Nährstoffaufnahme und Gehalte an Chlorophyll, Carotinoiden, Flavonoiden, Kohlenhydraten, Prolin und essentielle Ölen. DOI: 10.5073/JfK.2019.01.01, https://doi.org/10.5073/JfK.2019.01.01Rosemary is one of the most important medicinal plants. In order to study the effect of plant growth promoting rhizobacteria (PGPR), Azolla compost and Azolla biochar on dry matter, nutrient uptake, physiological parameters and essential oil of rosemary, a greenhouse experiment was conducted in a completely randomized design with 6 replications. Treatments consisted of T1 (control), T2 (1% (1 g 100 g-1 dry soil) Azolla compost), T3 (1% Azolla biochar), T4 (PGPR (P. fluorescens)), T5 (1% compost + PGPR) and T6 (1% biochar + PGPR). Results indicated a significant enhancement of dry matter, nutrient uptake, photosynthetic pigments, carbohydrate, flavonoid and essential oil contents of rosemary influenced by organic fertilizers compared to control, particularly with co-appli­cation of PGPR + compost or biochar. Proline content decreased in all treatments in comparison with control. Results indicated positive impacts of PGPR, compost and boichar of Azolla on rosemary production by increasing nutrient uptake and protecting chlorophyll from degradation and enhancing its content in leaves. DOI: 10.5073/JfK.2019.01.01, https://doi.org/10.5073/JfK.2019.01.0

Immobilization of Cadmium in a Cd-Spiked Soil by Different Kinds of Amendments

   Chemical stabilization of heavy metals is one of the soil remediation methods based on the application amendments to reduce mobility of heavy metals. A laboratory study was conducted to investigate the influence of different kinds of amendments on cadmium (Cd) stabilization in a Cd-spiked soil. The amendments were municipal solid waste compost (MSWC), Coal fly ash (CFA), rice husk biochars prepared at 300°C (B300) and 600°C (B600), zero valent iron (Fe0) and zero valent manganese (Mn0). The Cd-spiked soils were separately incubated with selected amendments at the rates of 2 and 5% (W/W) for 90 days at 25 °C. Soil samples were extracted by EDTA for periods of 5 to 975min. In addition, sequential extraction was used as a suitable method for identification of chemical forms of Cd and their plant availability. The addition of amendments to soil had significant effects on desorption and chemical forms of Cd. Changes in Cd fractions and their conversion into less soluble forms were clear in all treated soils. The addition of amendments resulted in a significant reduction in mobility factor of Cd compared to the control treatment. Among all amendments tested, Fe0 was the most effective treatment in decreasing dynamic of Cd. Biphasic pattern of Cd desorption kinetic was fitted well by the model of two first-order reactions. In general, from the practical point of view, Fe0, MSWC and Mn0 treatments are effective in Cd immobilization, while application of  Fe0 at 5% (W/W) was the best treatment for stabilization of Cd. </div