ABSTRACT
Seven isolates of fluorescent pseudomonads were evaluated for their effect on plant growth promoting traits, both under normal and saline conditions using tomato plants. Fifteen rhizosphere samples from crop fields' of rice, chilly, ragi, beans and garden soils from different regions of India were collected and used for further study. They were characterized morphologically and biochemically which led to a conclusion that they may belong to genus Pseudomonas. They were also analyzed for their plant growth promoting activities such as production of indole acetic acid, siderophore, hydrogen cyanide and ammonia. It was observed that all the isolates were able to produce these compounds, but to varying extent. But, isolate JUPF37 produced highest followed by JUPF32. Study showed that out of seven isolates of fluorescent pseudomonads, JUPF37 showed highest plant growth promoting traits both under normal and saline conditions.
Subject(s)
Pseudomonas/classification , Pseudomonas/isolation & purification , Soil Microbiology , Solanum lycopersicum/growth & development , Solanum lycopersicum/microbiology , Fluorescence , India , SalinityABSTRACT
Five fungal isolates were screened for the production of alpha-amylase using both solid-state and submerged fermentations. The best amylase producer among them, Aspergillus niger JGI 24, was selected for enzyme production by solid-state fermentation (SSF) on wheat bran. Different carbon and nitrogen supplements were used to enhance enzyme production and maximum amount of enzyme was obtained when SSF was carried out with soluble starch and beef extract (1% each) as supplements. Further attempts to enhance enzyme production by UV induced mutagenesis were carried out. Survival rate decreased with increase in duration of UV exposure. Partial purification of the enzyme using ammonium sulphate fractionation resulted in 1.49 fold increase in the enzyme activity. The enzyme showed a molecular weight of 43 kDa by SDS-PAGE. Metal ions Ca2+ and Co2+ increased the enzyme activity. The enzyme was optimally active at 30 degrees C and pH 9.5.
