MOLECULAR DIVERSITY AND CHARACTERIZATION OF DIAZINON MINERALIZING ENDOPHYTES FROM RICE PLANTS AND EVALUATION OF THEIR GROWTH PROMOTING TRAITS OF BRRI DHAN 28

Abstract

Plants are associated with vast and diverse group of microorganisms including bacteria, and fungus. Endophytic bacteria were used as biofertilizers and biocontrol agents for increasing croup cultivation. The purposes of present study was isolation and biomolecular characterization of diazinon pesticide degrading endophytes from rice plants and to evaluate there plant growth promoting properties. Synthetic, colorless liquid organophosphorus pesticide diazinon was used as sole carbon source in minimal salt media for isolation of target endophytes from the roots, shood and leaves of healthy Oryza sativa plants from two different aman rice field. By Screening of morphological characteristics F1LD1, F1LD2, F1LD3, F1SD1, F1SD2, F1SD3, F1RD1, F1RD2, F1RD3, F1RD4 were collected from field 1 and F2D1L, F2D2L,F2D3L, F2D1S, F2D2S,F2D3S, F2D1R, F2D2R,F2D3R, F2D4R were collected from field 2. They were characterized based on biochemical reaction, different cellulytic enzyme production, bioremediation, antagonism, invitro and invivo growth promotion potentials. All of them 12 endophytes were primarily selected for morphological characteristics by 16S gene sequence and 9 different genera of endophytic isolates were found as Pantoea sp(F1SD1), Burkholderia sp (F1RD4), Klebsiella sp (F1RD4), Pseudomonas sp (F2D1R), Bacillus sp (F2D2R), Enterobacter sp (F1LD2), Shigella sp (F2D3L), Kosakonia sp (F2D2L) and Serratia sp (F2D1S). In biochemical reaction oxidase catalase and triple suger iron agar test were shows positive reaction on the other hand indole gives negative reaction by all of isolates. Except F1RD4, F2D3L and F2D1R all other endophyte were give urease test positive. Thirteen of the isolates shows negative test for methyl red (MR) test, whereas fourteen of the isolates shows positive test for Voges- proskauer (VP). Seventeen of the isolates given MIU test positive on the other hand three isolates are given negative result are they F1RD1, F1RD2 and F2D1R. To assay fermentation of sucrose, lactose dextrose and maltose majority of endophytes were shows ablity to uses this carbohydrate as carbon source, only F1RD1 against sucrose and F2D1R against maltose shows negative result. All isolates produced xylanase, amylase and protease enzymes by liquefaction of the target medium but non of them can produce pectinase enzyme. Without F1RD2, F2D2L and F2D1S all other produce cellulose enzyme. The dye degradation assay represent that all isolated endophytes can survive 1% dye containing MSM medium by using avitera blue, bromothymol blue, toluidine blue, trypan blue and congo red as their sole carbon source. The FTIR spectrum of diazinon degradation by isolated endophytes give iii significant bioremediation potential. The significant antagonistics activity of isolated endophyts were also shows against huuman pathogenic bacteria S. Aureus and S. epidermidis. Out of the twenty isolates eighteen isolates can fix atmospheric nitrogen in the nitrogen free media. Eight of the isolates, LD2-F1, LD3-F1, SD3-F1, D1L-F2, D2L-F2, D1S-F2, D3S-F2 and D3R-F2 showed high growth with clear holo gone in Jensen’s medium. Without F1RD4 and F2D2R stain, all other isolated endophytes were capable of producing a halo/clear zone due to solubilization of inorganic phosphate in Pikovasky agar medium. F1RD2, F2D1S, F2D2S and F2D3S were can’t produce ACC deaminase plant hormone where as the IAA production ranged were investigate as 0.865– 8.718 mg/ml after the incubation of 72 hours. The seed germination % and vigorus index were significantly increased between the endophytes group than the control group. In vivo pot experiment of high yield rice variety BRRI dhan-28 by treatment of isolated endophytes shows high impact growth among shoot, root and dry weight. Pesticide degrading endophytes isolated from rice plants having a vital role to improve plant growth and could be used as biofertilizer and pesticide management tool to promote sustainable agriculture.