Showing 2 results for J. Yasrebi
J. Yasrebi, N. Karimian, M. Maftoun, A. Abtahi, A. Ronaghi, M. T. Assad,
Volume 7, Issue 4 (winter 2004)
Abstract
Twenty-five surface samples of calcareous soils of Fars Province were used to study the distribution of different nitrogen (N) forms to determine the relationship between the N forms and soil charcteristics, and to obtain regression equations for prediction of N forms from soil characteristics. The forms determined were: soil total nitrogen NO3-N by phenol disulfunic acid NO3-N extractable by 2 M KCl NH4-N extractable by 2 M KCl, 1 N sulfuric acid, and 0.25 N sodium hydroxide oxidative released N by acid permanganate and alkaline permanganate and NH4-N extractable by 2 M KCl at 100 oC. The highest amount of N was that released by alkaline permanganate which constituted 4.47% of soil total N and the lowest form was exchangeable NH4+ which amounted to only 0.6% of total N. Water soluble and exchangeable forms accounted for less than 2% of total N. Highly significant correlations were found between total N and acid permanganate-N (r=0.931) and total N and alkaline permanganate-N (r=0.850). Highly significant regression equations were obtained for prediction of soil total N, acid permanganate-N, and alkaline permanganate-N from soil organic matter (OM), which is an indication of a close relationship of these N forms with OM.
M. Zahedifar , N. Karimian , A. Ronaghi , J. Yasrebi , Y. Emam ,
Volume 14, Issue 54 (winter 2011)
Abstract
The effect of phosphorus (P) (0, 25, and 50 mg kg-1 soil as Ca(H2PO4)2) and organic matter (OM) (0, and 2% w/w feedlot cattle manure) on P and zinc (Zn) distribution in different parts of wheat plant (Triticum aestivum L.) at various growth stages and its relationship with soil P and Zn were determined in greenhouse condition. In all pots, shoot P concentration decreased as plant growth proceeded. Phosphorus concentration of shoot and flag leaf decreased from 7th to 9th stage of growth, whereas that of spickle increased. Spickle P uptake and Zn uptake of stem, shoot, flag leaf, and spickle increased with proceeding of wheat growth. Phosphorus uptake of shoot increased from 3th to 9th growth stages, whereas P uptake of stem and flag leaf decreased from 7th to 9th growth stages. Soil P and Zn concentrations increased with application of P and OM and plant growth. The trend of P and Zn changes in shoot, stem and flag leaf was similar. It is, therefore, concluded that analyzing flag leaf for P and Zn concentrations be used for prediction of plant nutritional status of those nutrient elements in cases where such information is needed.
