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Sekhon K.S.,PAU Regional Research Station | Singh J.P.,CCS Haryana Agricultural University | Mehla D.S.,CCS Haryana Agricultural University
Archives of Agronomy and Soil Science

A long-term experiment was used to evaluate the effect of integrated nutrient management on the distribution of soil organic N fractions and their contribution to N nutrition of a rice-wheat system. Continuous application of mineral fertilizers, alone or in combination with organic manures for 7 years, led to a marked increase in total N, hydrolysable N (amino acid-N, amino sugar-N, ammonia-N, hydrolysable unknown-N) and non-hydrolysable N compared with their original status in soil. However, continuous rice-wheat cropping without any fertilization resulted in depletion of total N, hydrolysable N and non-hydrolysable N by 21.3, 23.5 and 15.1% over their initial status in surface soil. The effect of press mud (PM) treatment was more pronounced in increasing total and hydrolysable N compared with farmyard manure (FYM) or green manure (GM) treatment. Incorporation of PM, FYM and GM along with mineral fertilizers increased the total N content by 32.8, 18.3 and 5.1% and that of hydrolysable N by 25.7, 19.6 and 9.5%, respectively, over mineral fertilizer treatment. Among the most important fractions, amino sugar-N, amino acid-N and ammonia-N were found to be most the important fractions contributing to grain yield and nitrogen uptake of rice and wheat crops. © 2011 Copyright Taylor and Francis Group, LLC. Source

Choudhary O.P.,Punjab Agricultural University | Brar J.S.,PAU Farm Advisory Service Scheme | Saroa G.S.,Punjab Agricultural University | Sekhon K.S.,PAU Regional Research Station
Journal of Crop Improvement

Response of wheat (Triticum aestivum L. emend. Fiori & Paol.) cultivars to irrigation with sodic waters having high residual alkalinity is not well known. The objective of this field investigation (2006-07 to 2008-09) was to study the response of three wheat cultivars (PBW 343, PBW 502, and PBW 550) to four levels of residual sodium carbonate (RSC) in irrigation water: 0, 3, 6.5, and 10 mmolc L-1 at Ludhiana. Another field study (2004-05 to 2006-07) involving PBW 343 and PBW 502 was carried out using tubewell water irrigation (RSC of 5.5 mmolc L-1) at Bathinda. Increase in RSC significantly increased soil pH and exchangeable sodium percentage and decreased grain yield of all three cultivars at Ludhiana. The three cultivars responded differentially to RSC levels. Data pooled across three years at Ludhiana revealed that at 3 mmolc L-1 RSC, yields of PBW 343 and PBW 502 were similar, but cultivar PBW 343 produced higher yield than PBW 502 and PBW 550 when irrigated with water containing 6.5 and 10 mmolc L-1 RSC. Cultivar PBW 550 had the lowest grain yields at all levels of RSC. Grain yield at 10 mmolc L-1 RSC was 3.9, 3.3, and 2.9 Mg ha-1 for PBW 343, PBW 502, and PBW 550, respectively. No significant effect of RSC of irrigation water on any grain quality parameter of cultivars was observed. At Bathinda, cultivar PBW 343 produced 11% higher grain yield than PBW 502 under tubewell irrigation. At both the locations, cultivar PBW 343 performed better with respect to yield than the other cultivar/s and, therefore, should be preferred on soils irrigated with waters containing RSC higher than 5 mmolc L-1. © 2012 Copyright Taylor & Francis Group, LLC. Source

Battu R.S.,Punjab Agricultural University | Mandal K.,Punjab Agricultural University | Urvashi,Punjab Agricultural University | Pandher S.,PAU Regional Research Station | And 2 more authors.
Bulletin of Environmental Contamination and Toxicology

A simple and efficient analytical method was standardized for the estimation of residues of carbaryl in various substrates comprising grape berries, kinnow pulps, kinnow rind and soil. The samples were refluxed using mixture of methanol: 0.5 N HCl (1:1 v/v); diluted with brine solution, partitioned into chloroform and dried over anhydrous sodium sulfate. Further the samples were treated with anhydrous magnesium sulfate and primary secondary amine. Final clear extracts were concentrated under vacuum and reconstituted the volume into acetone. The residues were estimated directly on gas liquid chromatograph equipped with nitrogen phosphorus detection system equipped with a capillary column packed with 5 % diphenyl 95 % dimethyl polysiloxane non-polar phase. A consistent recovery from 82 % to 97 % for carbaryl was observed when samples were spiked at levels ranging from 0.05 to 1.00 mg kg -1. The limit of quantification of the method was worked out to be 0.05 mg kg -1 for grape berries, kinnow pulp, kinnow rind and soil. © Springer Science+Business Media, LLC 2012. Source

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