Efficiency of Trichoderma harzianum Fungus in Bioremediation of Nominee and Superflak Pesticides Residues in Rice Fields in Najaf-Iraq

Abstract

The study included the use two isolates from Trichoderma harzianum that were used to biodegradation of the remaining pesticides. The comparison in petri dishes before and after adding pesticides. Were done the result showed a clear vegetative growth of fungi and their use of pesticides as an energy source. Scanning Electronic Microscope (SEM) was used to compare the vegetative growth of fungi before and after adding pesticides with PDA media, which showed a clear and natural growth with a short period of growth for a petri dish after addition pesticides compared to controlling for a petri dish at the magnification forces values (5446 x, 5955 x, 5998x, 6000 x, 6264x, 6754x) respectively. Spectrophotometer technique was used to estimate the total pesticides in the soil after 90 days of biological treatment with fungi. The results showed the highest biodegradation of superflak pesticide by Trichoderma harzianum (Th.16) which were 94.6%, the remaining superflak was 5.4%, and the degradation of the nominee pesticide percentage by the same isolation was 78.9%, the remaining nominee 21.1%, and the percentage of degradation by Trichoderma harzianum (Th.15) was the lowest percentage in the biodegradation of the nominee pesticide 76% and the percentage of the remaining nominee pesticide 24% and the percentage of biodegradation of the superflak by the same isolation was 92% and the percentage of the remaining superflak the remaining 8%. Spectrophotometer technique was used to estimate the total pesticides in PDB after 90 days of biological treatment with fungi. The results showed the highest biodegradation of Superflak pesticides by Trichoderma harzianum (Th.15) 94.7%, the remaining superflak 5.3%, and the biodegradation percentage of nominee by the same isolation 76%, the remaining nominee 24%, and the percentage of biodegradation of the nominee pesticide by Trichoderma harzianum (Th.16) was the lowest percentage in the biodegradation 86.9% and the percentage of the remaining nominee pesticide 13.1% and the percentage of biodegradation of the superflak by the same isolation 81% and the percentage of the remaining superflak the remaining 19%.