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The major storage form of phosphorus in mature cereal and legume seeds is phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, InSP6) which binds metallic cations such as calcium, zinc, magnesium and iron to form a mixed salt called phytate. Thus, phytates act as anti-nutrients, rendering the minerals unavailable. Myo-inositol phosphate synthase(MIPS) is the major gene for phytate synthesis in legumes and it is characterized only in few major legumes such as soybean, green gram, black gram, cowpea and french bean. Even though dolichos bean is the legume with the highest content of phytic acid (1000–1350 mg/100 g), MIPSgene from this important crop is not characterized yet. For the strategies such as RNA mediated gene silencing, which is potential enough to reduce the level of phytates in crops, mRNA sequence should be completely known. For this purpose, RNA was isolated from the developing seeds and dolichos MIPS cDNA was isolated using one-step RT-PCR system with high fidelity DNA polymerase. From this, dlMIPSgene was cloned and sequence characterized. Gene dlMIPScomprised of 1776 bp with an ORF of 1620 bp, which encodes 539 amino acids. Phylogenetic analysis of the sequence had shown that dolichos bean is closer to green gram, cowpea and french bean. Secondary and tertiary structures of the enzymes from dolichos bean, cowpea and french bean were predicted through homology modeling and compared. Subsequent prediction and comparative analysis of the active sites of enzyme from these legumes had shown that the ligand binding residues vary among legumes.

Background: Entomopathogenic nematodes (EPNs) belonging to the Heterorhabditisspp. harbour symbiotically associated bacteria which are toxic to a wide range of insect pests. Isolation, purification, characterization and mass multiplication of such bacteria will be a promising strategy in the management of the pests. This study was carried out to isolate the EPN from different locations, isolate and purify the bacterial colonies, characterize the bacteria through morphological and molecular strategies and to test the efficacy of different bacteria in the control of polyphagous Tetranychus truncatusEhara mites. Results: EPNs were isolated from soil samples at 11 localities of Kerala State, India, and used to infect the Galleria mellonellaL. larvae. Bacteria associated with the haemolymph of the infected larvae were isolated, which on NBTA medium have produced circular to irregular, entire, opaque and smooth colonies. Sequence characterization of the 16S rRNArevealed nine isolates namely: one symbiotic bacterium Photorhabdus luminescens, two Pseudomonas aeruginosa, five Ochrobactrumsp. and one Stenotrophomonas maltophilia.Phylogenetic analysis using the sequences has further confirmed the bacterial identity. Evaluation of the cell suspension (CS) and cell-free supernatant (CFS) of P. luminescens, P. aeruginosaand Ochrobactrumsp. for their adulticidal and ovicidal efficiencies on T. truncatushad identified significant adulticidal effects by P. luminescens,followed by P. aeruginosa.After 96 h of treatment, P. luminescensat 108cells/ml resulted in a significantly higher mortality rate of adult mites (64.00 and 60.67%, respectively, for CFS and CS), compared to that resulted by P. aeruginosa(38.67 and 33.33%). Conclusions: Results of this study showed that P. luminescensassociated with the EPN Heterorhabditisspp. is a promising biocontrol agent for T. truncatus.