Characterization of commercial humic acid samples and their impact on growth of fungi and plants

Lodhi, Asma; Tahir, Shermeen; Iqbal, Zafar; Mahmood, Ansar; Akhtar, Muhammad; Mahmood Qureshi, Tariq; Yaqub, Muhammad; Naeem^Nuclear, Asif
June 2013
Soil & Environment;Jun2013, Vol. 32 Issue 1, p63
Academic Journal
Naturally occurring humates like leonardite and brown coal or lignite are marketed under different brand names e.g. Pak Humates, Humate Fertilizer, Pak Humax, Humkara and Hum ide etc. However, their efficacy is needed to be confirmed before their use. Different studies were conducted for the comparison of four commercial humates for their physico-chemical, optical properties, plant growth promoting ability in terms of seed germination and seedling vigour in wheat (cv Sehr), mung bean (Mung-54), maize (C-12) and sesbania and their effect on growth of some fungi. Moisture content of four humates varied from 0.52 to 71.11%, while solubility in water varied from 30.2 to 98.2% and density differed from 1.67 to 4.17. A 2% solution of humates hadpH and EC varying from 5.39 to 10.11 and 3.140 to 1.143 mS cm-1, respectively. Carbon and nitrogen concentrations varied from 22.95 to 36.56% and 0.658 to 1.183, respectively with a C/N ratio of 30.91 to 44.16. Humates dissolved in 0. IN NaOH were partitioned into humic acid and fulvic acid fractions. Of the total C in humates, 40.3 to 77.5% was ranged in humic acid and 22.5 to 59.7% infulvic acid fraction. The HA was also studied for optical properties at 400, 500, 600, and 700 nm besides that at 465 and 665 to calculate E4/E6 (extinction coefficient); the later varied between 3.64 and 5.48. Optical density of the humic acid decreased at increasing wavelength and was correlated significantly with the carbon contents of humic compounds. Three fungi, Trichoderma harzianum, T. hamatum and Alternaria alternata showed maximum growth at 0.025% HA in the growth medium on the basis of colony diameter. Humates inhibited seed germination in wheat, maize and mung bean exceptfor sesbania. Root length and shoot thy matter increased in wheat and maize but no effect was found in mung bean and sesbania. The studies revealed that humates available in the market vary widely and therefore some sort of quality monitoring is required for the benefit of end users.


Related Articles

  • Selective extraction of humic acids from an anthropogenic Amazonian dark earth and from a chemically oxidized charcoal. Araujo, Joyce; Archanjo, Braulio; Souza, Katia; Kwapinski, Witold; Falcão, Newton; Novotny, Etelvino; Achete, Carlos // Biology & Fertility of Soils;Nov2014, Vol. 50 Issue 8, p1223 

    Spectroscopic techniques including X-ray photoelectron spectroscopy (XPS) can identify particular chemical groups of humic acids (HA) from 'Terra Preta de Índios' (TPI) or Amazonian dark earth, the highly fertile anthropogenic soil found in the Amazonian region. The high fertility and...

  • Influence of humic acid applications on modulus of rupture, aggregate stability, electrical conductivity, carbon and nitrogen content of a crusting problem soil. Gümüş, İ.; ¸Seker, C. // Solid Earth;2015, Vol. 6 Issue 4, p1231 

    Soil structure is often said to be the key to soil productivity since a fertile soil, with desirable soil structure and adequate moisture supply, constitutes a productive soil. Soil structure influences soil water movement and retention, erosion, crusting, nutrient recycling, root penetration...

  • Humic acids in brown coals from the southern Russian Far East: General characteristics and interactions with precious metals. Avramenko, V.; Bratskaya, S.; Yakushevich, A.; Voit, A.; Ivanov, V.; Ivannikov, S. // Geochemistry International;May2012, Vol. 50 Issue 5, p437 

    Brown coals with high Au and PGE concentrations from six deposits in the southern Russian Far East were analyzed for elemental composition, acid-base properties, and the molecular-size distribution of humic acids (HA). The ash contents of the coals were determined to be negatively correlated...

  • MEASURING THE HUMIC ACIDS CONTENT OF COMMERCIAL LIGNITES AND AGRICULTURAL TOP SOILS IN THE NATIONAL SOIL PROJECT. Ghabbour, Elham A.; Davies, Geoffrey; Daggett Jr., John L.; Worgul, Christopher A.; Wyant, Gregory A.; Sayedbagheri, Mir-M. // Annals of Environmental Science;2012, Vol. 6, p1 

    Radiocarbon dating studies have demonstrated that soil organic matter (OM) consists of two pools: a labile, short-lived pool that is an energy source for microbes, and a much longer-lived humic substances (HS) pool that is protected from microbial attack and represents the sequestered carbon in...

  • Electric condensation of divalent counterions by humic acid nanoparticles. van Leeuwen, Herman P.; Town, Raewyn M. // Environmental Chemistry (14482517);2016, Vol. 13 Issue 1, p76 

    Experimental data for divalent counterion binding by soil humic acid nanoparticles are set against ion distributions as ensuing from continuous Poisson-Boltzmann electrostatics and a two-state condensation approach. The results demonstrate that Poisson-Boltzmann massively underestimates the...

  • EFFECT OF POST-HARVEST MOWING ON STRAWBERRY 'DARSELECT' GROWTH AND YIELD GROWN ON PLASTIC MULCH. Rätsep, Reelika; Karp, Kadri; Vool, Ele // Research for Rural Development - International Scientific Confer;2015, Vol. 1 Issue 1, p51 

    The experiment was carried out at the Research Centre of Organic Farming of Estonian University of Life Sciences in 2012 and 2013. The study was aimed to find out the effect of defoliation and humic acid application on the strawberry (Fragaria × ananassa Duch.) plant growth, yield, and on...

  • Revisited: DGT speciation analysis of metal-humic acid complexes. van Leeuwen, Herman P. // Environmental Chemistry (14482517);2016, Vol. 13 Issue 1, p84 

    Soil humic acids and their metal complexes are sorbed by hydrogel phases such as those used in DGTanalysis. The accumulation is spatially inhomogeneous: a thin film near the interface with the aqueous medium typically hosts ~10 times the concentration in the medium, whereas the bulk gel features...

  • Preparation and characterization of bioactive products obtained via the solubilization of brown coal by white rot fungi. Klein, O.; Kulikova, N.; Stepanova, E.; Filippova, O.; Fedorova, T.; Maloshenok, L.; Filimonov, I.; Koroleva, O. // Applied Biochemistry & Microbiology;Dec2014, Vol. 50 Issue 7, p730 

    We investigated the solubilizing activity of the Basidiomycete fungi Trametes hirsuta and Trametes maxima, with respect to brown coal (lignite) during liquid phase cultivation. We found that the degrading capacity of the fungi is determined by the activity of the ligninolytic enzymes Mn...

  • Effect of developmental stage on some maturity parameters of plantain fruits. Onuegbu, Ngozika; Ubbaonu, Collins; Ajoku, Nkeiru; Ihediohanma, Ngozi // Nature & Science;Sep2011, Vol. 9 Issue 9, p68 

    The physical characteristics and total soluble solids of plantain fruits fingers were measured weekly starting from the 6th week after fruit set until ripening. This work was aimed at determining the appropriate time of harvest for the mature plantain fruit in order to obtain maximum yield. The...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics