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Traditional organic formulations are widely used as a plant growth promoters; however, the knowledge on the microbial aspect of traditional organic formulations is still limited. The aim of this study was to illustrate the cultivable bacterial diversity of various traditional organic formulations and their potential for early plant growth promotion. Five different traditional organic formulations such as 100 % panchagavya, 33 % panchagavya, plant extract with native microorganisms, commercial organic fertilizer extract with two percent leaf soil extract and commercial organic fertilizer extract with 2 % yogurt were prepared and used in this study. The liquid fraction of these traditional organic formulations were used to analyze the beneficial effect on plant growth by seed treatment and foliar applications. Bacterial 16SrDNA analysis revealed that the isolates fell into forty-three different genera, which can be grouped into seven different classes, such as Alphaproteobacteria, Actinobacteria, Bacilli (or Firmibacteria), Betaproteobacteria, Cytophagia, Flavobacteriia and Gammaproteobacteria. Higher bacterial diversity was observed in cow dung followed by 33 and 100 % panchagavya. Radish and Chinese cabbage seed germination and growth were significantly improved by traditional organic formulations compared to control. The results of this study showed that the bacterial diversity changes depend on the type and concentration of ingredients used in traditional organic formulations. Substantial increase in plant growth by the traditional organic formulations indicates the suitability of using these organic preparations in eco-friendly agriculture.

Molecular markers are the fragments of DNA sequences associated with the genome that are used to identify particular DNA sequence. Markers are very much useful in the identification of microorganisms and in determining plant microbe interactions. This chapter deals with the molecular markers used in the diagnosis of Arbuscular Mycorrhizal Fungi (AMF). Conventional methods of AMF identification and classification have been done with the spore characters such as size, colour, spore wall layer, spore-hyphal attachment and spore germination. However, the problem associated with the availability of well-trained taxonomist and the difficulties in distinguishing the minor differences in the spore wall layers mislead the identification. Nowadays, with the explosive growth of genetic research and marker development improved our knowledge on AMF identity, diversity, role in the ecosystem functioning and plant growth promotion. Molecular markers may be grouped into non-PCR and PCR based approaches. Each of them has their advantages and disadvantages. Therefore, different markers are needed for the identification of AMF. It has been reported that combining two or more genetic markers to identify or classify AMF are more reliable than using single marker. Many molecular markers are biased, as some of the primers used to detect only parts of the community and the level of taxonomic resolution in most cases are uncertain. Species-level community analyses based on rDNA regions should be feasible, but no single molecular marker or DNA barcode is yet suitable for species-level resolution of all AMF genera. Discovery of new molecular markers (DNA or non-DNA based), in the field of AMF identification and plant-AMF interactions are very much desirable.

Cellulase finds use in saccharification of lignocellulosic agroresidues to fermentable sugars which can be used for production of commercially important metabolites. This study reports endoglucanase (CMCase) production by Enhydrobacter sp. ACCA2. The CMCase activity of the strain ACCA2 was successively improved by optimization of range of physical and nutritional parameter in a set of non-statistical and statistical experiments. Initial non-statistical selection of carbon source, incubation time, temperature and pH resulted in 1.07 fold increase of CMCase activity. In a subsequent statistical method, response surface methodology, optimization of medium components such as carboxymethylcellulose, peptone, NaCl, MgSO4•7H2O, FeSO4•7H2O, K2HPO4 and (NH4)2SO4 yielded further increase up to 2.39 fold CMCase activity. The cellulolytic potential was evaluated in biomass saccharification with different plant materials and the results revealed that the enzyme produced by strain may have significant commercial values for industrial saccharification process. Moreover, this is the first report of cellulase production by an Enhydrobacter spp.