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The objective of the study was to assess the 32 years impact of long-term manuring and fertilization on soil organic C (SOC) pools and stocks under rice-wheat cropping system in an Inceptisol and compare different methods for estimation of labile and resistant SOC pools. The treatments included control (T1), 100% NPK- fertilizer (T2), 50% NPK + 50% N-FYM (T3), 75% NPK + 25% N-FYM (T4), 50% NPK + 50% N-wheat straw (WS) (T5), 75% NPK + 25% N-WS (T6), 50% NPK + 50% N-green manure (GM) (T7), and 75% NPK + 25% N-GM (T8). The soil samples were analyzed for SOC, oxidizable and resistant C by hot water (HWEC, HWRC), KMnO4 (KMnO4-Cox, KMnO4-Cres), NaOCl (NaOClox, NaOCl-Cres), bulk density. As compared to 100% NPK, the SOC stocks (0–60 cm) in T3, T5, and T7 were increased by 10, 9.3, and 5.6%, respectively. The mean NaOCl-Cox, C mineralization (Cmin), HWEC, and KMnO4-Cox stocks contributed 37, 11, 6, and 4% of SOC stock. The correlation study showed that Cmin positively correlated with KMnO4-Cox, HWEC, and NaOClox. For assessing the mineralizable SOC pool, NaOCl-Cox overestimated, while HWEC and KMnO4-Cox underestimated it. Thus, these protocols need to be modified to match the Cmin data. However, NaOClox is recommended for assessing mineralizable SOC over 90 days of incubation. [ABSTRACT FROM AUTHOR]

The aim of present study was to investigate the antimicrobial activity of Cenchrus ciliaris and Cenchrus setigerus extracts in order to use it as a possible source for new antimicrobial substances against important human pathogens. Crude extracts of the stem of Cenchrus ciliaris and Cenchrus setigerus were evaluated against some medically important pathogens viz. Escherichia coli, Raoultella planticola, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Enterobacter aerogenes, Candida albicans and Aspergillus lavus. The dried and powdered stems were successively extracted with hexane, toluene, isopropyl alcohol, acetone and ethanol using soxhlet assembly. The antimicrobial activity assay was done by both disc diffusion and serial dilution methods. Isopropyl alcohol extract of Cenchrus setigerus showed highest activity against Escherichia coli. The test pathogens were more sensitive to the isopropyl alcohol, acetone and ethanol extracts than to the hexane and toluene extracts except against Bacillus subtilis. Result reveals that the most bioactive compound was cycloleucolenol-9,19-cycloergost-24 (28)-en-3-ol, 4, 14-dimethyl acetate in both the species of Cenchrus grass, (19.15%) in isopropanol extract of Cenchrus setigerus whereas, (14.03%) in acetone extract of Cenchrus ciliaris. [ABSTRACT FROM AUTHOR]