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Summary Among several phosphate-solibilizing micro-organisms isolated from an alluvial soil (Fluvaquent) in sucrose-Ca3(PO,~) 2 agar plates, two fungal strains, ACF2 (Aspergillus eandidus) and ACF Z (A. fumigatus) two bacterial strains, ACB s (Baeillusfirmus B-7650) and ACB~ (B. firmus B-7651) and one actinomycete strain, ACSo (Streptomyces sp.) were efficient solubilizers, solubilizing 297.0, 288.3, 49.0, 45.8 and 29.0 p.g of P as free PO4 -3, respectively, containing 15 mg insoluble P from Ca3(PO4) 2 in broth. Solubilization was lesser from A1PO 4 and FePO 4. The isolates producing oxalic and tartaric acids without or with citric acid showed higher ability of solubilizing insoluble inorganic phosphates.All the above isolates possessed the ability of solubilizing rock phosphate in considerable amounts, ACF 1 (A.fumigatus) being the highest (31.5 p.g), while ACB 6 (B.firmus B-7651) and both the aspergilli also possessed cellulose-decomposing ability in addition. Inoculation of the isolates, in a flask culture experiment, had no significant effect on the accumulation of available phosphorus in soil even when amended with rock phosphate (RP), farm yard manure (FYM), (FYM + RP), rice straw (RS) and (RS + RP). Nevertheless, the overall performance ofACF 2 (A. candidus) and ACB 6 (B.firmus B-7651) was better than that of the others, in this respect, while ACB 5 (B. firmus B-7650) and ACF 1 (A. fumigatus) intensified the enhancing effect of FYM and RS. Partial sterilization, by autoclaving, of the soil had no significant effect on available phosphorus content of the soil irrespective of any inoculation.

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A total of 1,367 first lactation records of daughters of 81 sires, having 5 or more progeny were used to evaluate sires by 3 different methods viz., least squares (LS), best linear unbiased prediction (BLUP) and derivative free restricted maximum likelihood (DFREML) method. The highest and lowest overall average breeding value of sires for first lactation 305 days or less milk yield was obtained by BLUP (1,520.72 kg) and LS method (1,502.22 kg), respectively. The accuracy, efficiency and stability of different sire evaluation methods were compared to judge their effectiveness. The error variance of DFREML method was lowest (191,112 kg 2 ) and its coefficient of determination of fitting the model was highest (33.39%) revealing that this method of sire evaluation was most efficient and accurate as compared to other methods. However, the BLUP method was most stable amongst all the methods having coefficient of variation (%) very near to unadjusted data (18.72% versus 19.89%). The higher rank correlations (0.7979 to 0.9568) between different sire evaluation methods indicated that there was higher degree of similarity of ranking sires by different methods ranging from about 80 to 96 percent. However, the DFREML method seemed to be the most effective sire evaluation method as compared to other methods for the present set of data.

Summary A super strain of Bacillusfirmus (NCIM-2636) producing a phytohormone, indole-3-acetic acid, in addition to its high ability to solubilize insoluble inorganic phosphates were applied in acid soils of Nagaland, India. Rice (Oryza sativa L.) variety Jaya and IR-8 were grown in kharif season in two successive years 1980 and 1981. After proper manuring the soils received single super phosphate (S.S.P.) and Mussoorie Rock phosphate (R.P.) separately at different doses. Yield of crop in both the years increased significantly due to bacterial inoculation. Maximum grain yield was recorded in Jaya variety under S.S.P. and R.P. when treatments were at the dose of 43.75 and 17.5 kg P ha-1 respectively while the same in IR-8 variety under S.S.P. and R.P. treatments were at the dose of 35 and 17.5 kg P ha-1 respectively. Maximum straw yield was produced by Jaya variety when 35 and 43.75 kg P ha-1 in the form of S.S.P. and R.P. respectively were applied. Highest straw yield of IR-8 variety was obtained after the application of 17.5 kg P ha-1 (S.S.P. and R.P.) in combination with phosphate solubilizing bacteria. Bacterial inoculation decreased the phosphorus availability in 1 st year but increased the same in 2nd year. Phosphorus content in grains was significantly enhanced in both the trials. Maximum uptake of phosphorus by grains was noted in Jaya variety at the dose of 47.5 kg P ha-1 and in IR-8 variety at the dose of 52.5 kg P ha-1 under S.S.P. treatment, while 8.75 and 35 kg P ha-1 in the form of R.P. yielded similar results in Jaya and IR-8 varieties respectively. Phosphorus at the dose of 35 kg ha-~ was found to cause more P-uptake by straw in both S.S.P. and R.P. treatments. The various data from the experiment conclusively proved that the bacterium in combination with R.P. produced the desired effect more prominently than when bacterium applied in combination with S.S.P.

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