Humic acids were extracted from cattle, food and paper-waste vermicomposts using an alkali/acid fractionation procedure which produced 1 g dry wt humates from 400 g vermicompost. They were applied to a soilless growth medium, Metro-Mix 360 (MM360), at rates of 0, 250 or 500 mg humates kg–1 dry wt of container medium, to young marigold, pepper, and strawberry plants grown in pots in the greenhou...

Granular and liquid commercial humates, with micronutrients, and a microbial fermentation product were compared in several combinations with nematicides for their effects on cotton lint yield and root-knot nematode suppression. Fumigant nematicides effectively reduced cotton root galling caused by root-knot nematodes, and cotton lint yields increased. Organophosphates and carbamates were not ef...

The type and amount of organic matter present in industrially contaminated soils will influence the risk they pose. Previous studies have shown the importance of humic and fulvic acids (FAs) (important components of soil organic matter) in increasing the solubility of toxic metals but were not carried out using toxic metal levels and the pH range typical of industrially contaminated soils. This...

The complexity of humic substances and their remarkable properties have attracted and continue to attract the attention of many investigators, bringing over the years new knowledge on their structure, physicochemical and biological properties pointing to the use of these interesting natural compounds in many practical applications. The numerous investigations produced, up to now, controversial ...

Possible enhancement of biodegradation of petroleum hydrocarbons in agricultural soil after tank truck accident (~5000 mg/kg dry soil initial concentration) by bioaugmentation of diesel degrading Pseudomonas fluorescens strain and addition of abiotic additives (humates, zeolite) was studied in a 9-month pot experiment. The biodegradation process was followed by means of analytical parameters (h...

The supply of iron to plant roots was one of the main problems in water culture until about 1950. The main source of iron was originally ferrous sulfate, already used by Sachs (9). It had to be supplied almost daily to the nutrient solution as it precipitates gradually. Some improvement was obtained with organic compounds, mainly ferric citrate, introduced by Gile and Carrero (4). The favorable...

Humic substances are generally seen as important soil and natural water components. They are formed during humification of organic matter by soil microorganisms. Humic substances are a mixture of complex organic compounds that are usually separated into three fractions: humic acids, fulvic acids and humins. The properties of humate products on the market depend on the ratios between these fract...