Effect of simazine,lindane and ceresan on soil respiration and nitrification rates

Summary The effect of three pesticidesviz, simazine, lindane and ceresan upto 100-fold of field application was studied on organic matter mineralization as well as on nitrification rates in Delhi alluvial soil. The normal rate of simazine (2 ppm) did not influence CO₂ evolution but higher concentrations suppressed it. Lindane and ceresan inhibited CO₂ production from soil by normal concentrations but the same CO₂ production was enhanced in berseem roots treated soil upto 10 ppm of ceresan.The nitrification of ammonium sulphate in soil due to these pesticides was impaired significantly for varying periods. The inhibitory effect of higher concentrations was marked only upto 3 weeks, subsequently the rate of nitrification was restored. Among the nitrifiers, Nitrobacter were more susceptible as compared to Nitrosomonas.     

Electron microscopy of some rock phosphate dissolving bacteria and fungi

BacteriaPseudomonas striata, Bacillus polymyxa, B. megaterium andB. pulvifaciens, and fungiAspergillus awamori, A. niger andPenicillium digitatum dissolve tricalcium phosphate and, much less, Mussorie and Udaipur rock phosphate. The solubilizing power of fungi was higher than that of bacteria, the highest being withA. awamori andA. niger, and withP. striata. Electron microscopy of the various cultures showed an electron-dense layer on the bacterial surface after negative staining. The size of phosphate particles decreased by the microbial action, with tricalcium phosphate from 140 — 250 to 30 — 90 nm after three weeks of incubation.     

Effect of ‘Mixtalol’ on growth,yield and yield components of Indian mustard (Brassica juncea)

Mixtalol (a mixture of long chain aliphatic alcohols varying in chain length from C₂₄ to C₃₂) applied to Brassica juncea plants as foliar spray caused an increase in secondary and tertiary branching with consequent enhancement in seed yield through increased number of inflorescences and siliquae per plant. The percentage of immature siliquae and shattering of siliquae decreased with this treatment. Mixtalol increased total dry matter of plants, partitioning coefficient and harvest index. The contents of starch, protein and oil were also higher in seeds from Mixtalol treated plants.     

Metabolic compensation activates pro-survival mTORC1 signaling upon 3-phosphoglycerate dehydrogenase inhibition in osteosarcoma

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The effect of humic and fulvic acids on the growth and efficiency of nitrogen fixation ofAzotobacter chroococcum

Humic acid in the form of sodium humate and fulvic acid markedly increased the growth and efficiency of nitrogen fixation ofAzotobacter chroococcum. Fulvic acid proved more effective than the sodium humate. The effectiveness of these substances was more pronounced in increasing the number of cells than affecting the nitrogen fixation. The increases in growth and nitrogen fixation were in direct proportion to the quantities of sodium humate and fulvic acid applied up to 500 and 700 ppm respectively. Thereafter the growth was restricted, although it was not inhibited even at 1,400 ppm.