35.Islas-Pelcastre, M., Madariaga-Navarrete, A., Castro-Rosas, J., González-RamÍrez, C.A., Acevedo Sandoval, O. and Villagómez-Ibarra, J.R. 2013. Bioremediation perspectives of agricultural soil from Tulancingo Valley, México, with Trichoderma sp. native to degrade atrazine. Tropical and Subtropical Agroecosystems. 16:265-276
The objective of this study was to show an in vitro bioremediation methodology for atrazine-contaminated soils through the use of local strains of native fungi isolated from the Phaseolus vulgaris L rhizosphere present in cultivable soils as well as to evaluate its resistance and capacity for atrazine degradation. A Trichoderma sp. species was identified in three cultivable soils from the Tulancingo Hidalgo, México region (contaminated with and without atrazine), which resisted atrazine concentrations of 10,000 mg L-1. Tests showed that the strain grows exponentially in atrazine-contaminated soil over a range of 105-106 CFU g-1 in 15 days using atrazine as the only carbon and nitrogen source, while the control and witress showed a decrease of 100-103 UFC g-1 in the same period of time. For the atrazine degradation experiments, a treatment of the application of Trichoderma (104 - 105 CFU mL-1) was applied to sterilized and non-sterilized soil contaminated with 500 mg Kg-1 of atrazine, evaluated at four time intervals (5, 10, 20 and 40 days). Statistical differences were found (?=0.050, Tukey) among treatments with the fungi and the test days. The native Trichoderma strain degraded 89% of the atrazine in 40 days. It showed that it is viable and cultivable in soil bioremediation.