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Nine isolates of Trichoderma spp. were investigated for their ability to solubilize insoluble phosphate in Pikovskaya's broth and were compared with an efficient phosphate-solubilizing bacterium Bacillus megaterium subsp. phospaticum PB that was used as the reference strain. All 9 Trichoderma isolates were found to solubilize insoluble tricalcium phosphate to various extents. Trichoderma viride (TV 97) (9.03 microg x mL(-1)), Trichoderma virens (PDBCTVs 12) (9.0 microg x mL(-1)), and Trichoderma virens (PDBCTVs 13) (8.83 microg x mL(-1)) solubilized 70% of that solubilized by the reference strain Bacillus megaterium (12.43 microg x mL(-1)). Pot culture and field evaluations with Trichoderma harzianum (PDBCTH 10), Trichoderma viride (TV 97), and Trichoderma virens (PDBCTVs 12) using chickpea (Cicer arietinum L.) 'Annegeri-1' as the test plant and rock phosphate as the phosphorus source showed significantly increased P uptake in plants treated with Trichoderma harzianum (PDBCTH 10) followed by Trichoderma virens (PDBCTVs 12) and Trichoderma viride (TV 97). Inoculation of Trichoderma spp. also showed increased growth and yield parameters of chickpea compared with the uninoculated controls under both glasshouse and field conditions.

Growth pattern and biochemical composition of three species of Spirulina, S platensis, S laxissima and S lonar, were studied under controlled culture conditions. The chemical constituents were analysed in terms of chlorophyll-a, phycobilliproteins, β-carotene and phenolics (intracellular and extracellular). Of the three species S platensis showed highest growth rate, biomass, pigment concentration and low intracellular phenolics. The shortest doubling time was seen in S platensis. The results demonstrated the importance of strain selection for large-scale cultivation. The results also showed differences in culture conditions (light intensity and pH) for the three species of Spirulina to obtain the maximum growth, as well as biochemical basis for obtaining the maximum growth in Spirulina spp.

The shoot and fruit borer, Earias vittella is one of the major polyphagous pest prefer various host plants attacking almost 38 plant species and causes yield loss of 15-45% in vegetable crops annually in India. In this study Entomopathogenic bacteria (EPB) were used for biocontrol larvae of Earias vittella under in vitro condition. Whole cell culture and cell supernatant of EPB was screened for insecticidal activity against the larvae and results has shown that the lethality of larvae started after 12-24h of treatment. The percent mortality treated with intact cell was significantly higher in larvae treated with EPB3 with 90% mortality at 72h followed by EPB1 and EPB3. The larvae treated with cell supernatant of EPB had shown lethality in the range of the mortality of larvae where in the range of 50-70% at 72h of treatment and there was no significant difference among the bacteria treated. The LD50 value represent the concentration of cells required for the 50% population to be lethal and EPB3 had expressed significantly lower concentration of 4.28x10 4 CFU / ml followed by EPB9 and EPB8. The LD50 value for the larvae treated with cell supernatant were in the range of 10 10 to 10 12 CFU / ml. The larvae treated with EPB3 cell culture has taken significantly less time for mortality of fifty percent of population with a media lethal time (LT50) of 24h followed by EPB1 (30h) and EPB8 (32h). Among all the isolates EPB3 (Xenorhabdus nematophila) and EPB1 (Photorhabdus luminescens) had more virulence against the Earias vittella and can be further tested for biocontrol efficiency under greenhouse and field conditions.

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