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An intracellular glucose oxidase (GOD) was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger NFCCP. The enzyme was partially purified to a yield of 28.43% and specific activity of 135 U mg(-1) through ammonium sulfate precipitation, anion-exchange chromatography, and gel filtration. The enzyme showed high specificity for D-glucose, with a K(m) value of 25 mmol L(-1). The enzyme exhibited optimum catalytic activity at pH 5.5. Optimum temperature for GOD-catalyzed D-glucose oxidation was 40 degrees C. The enzyme displayed a high thermostability having a half-life (t(1/2)) of 30 min, enthalpy of denaturation (H*) of 99.66 kJ mol(-1), and free energy of denaturation (G*) of 103.63 kJ mol(-1). These characteristics suggest that GOD from A. niger NFCCP can be used as an analytical reagent and in the design of biosensors for clinical, biochemical, and diagnostic assays.

Azospirillum lipoferum strain (GQ 255949) exhibits the ability to mitigate stress conditions. The present study was carried out to evaluate the biocontrol and salt tolerance potential of A. lipoferum and to examine its ability to mitigate salt stress in wheat crop when inoculated. A. lipoferum has shown strong biocontrol potential against Aspergillus niger and Pseudomonass spp. Strain exhibited the survival efficiency uptill 150 mM NaCl and also showed production of different osmolytes such as proline, soluble protein, soluble sugars and Super oxide dismutase while growing under saline conditions. Although salinity affected growth and metabolism of wheat, A. lipoferum inoculation significantly ameliorated its effects by improving the germination and plant growth, particularly under higher salinity levels (50 mM, 100 mM and 150 mM NaCl). Maximum impact of inoculation was observed at 150 mM NaCl. Chlorophyll content and membrane stability improved with inoculation resulting in 38.6% and 15.3% at 150 mM NaCl. Highest increase in concentration of osmolytes was 35.6% in proline, 28% in soluble sugars, in inoculated plants as compared an un-inoculated wheat plant under saline condition. It is concluded from the present findings that A. lipoferum strain (GQ 255949) has potential to promote growth of wheat plants under saline conditions.

Identification of genetic factors responsible for controlling germination traits under salinity will allow developing tolerant cultivars. Here we have studied quantitative trait loci (QTL) linked to seed germination and early seedling growth traits using recombinant inbred lines generated from crossing of wheat cultivars, Pasban 90 (salt tolerant) and Frontana (salt susceptible). QTL analysis were done using composite interval mapping (CIM) for germination percentage (G%), germination index (GI), seedling vigor index (SVI), shoot length (SL), root length (RL), fresh wight (FW) & dry weight (DW). In this QTLs analysis total 44 QTLs were identified, 26 QTLs out of 44 were identified in 150 mM salt stressed and eighteen QTLs under control environment. Eleven main quantitative trait loci (QTLs) were localized on 1B, 2B, 3B, 5B, 6B and 7B chromosome of mapping population in stressed environment. QTLs mapped on 6A, 3B, 6B and 6D chromosome for root and shoot length, fresh and dry weight were recognized as a major QTLs under control treatment. QTLs for root and shoot length were mapped on 2D same position in xgdm36-xwmc111. Root length and dry weight QTLs was flanked in interval of xgwm70-xgwm325 markers on 5B chromosomes. The result of this study revealed that QTLs play main role in salt tolerance at seed germination and early seedling growth stage.