Soil crops

Micronutrients. Attention to meeting the micronutrient needs of crops has greatiy increased as evidenced in an analysis undertaken by TVA and the Soil Science Society in 1972 (99). The micronutrient elements most often found wanting in soil—crop situations are boron, copper, iron, manganese, molybdenum, and zinc. Some of these essential micronutrients can be harmful to plants when used in excess. 

Figure 8 The effect of fertilizer application and rainfall and the emissions of NO and N,0 from clay loam soils cropped with ryegrass cut for silage in South Scotland.

P. de Willigen, Nitrogen turnover in the soil crop system—comparison of 14 simulation models. Feitil. Res. 27 141 (1991). 

R. F. Grant, The distribution of water and nitrogen in the. soil-crop system a simulation study with validation from a winter wheat field trial. Fertil. Res. 27 199 (1991). 

A plefhora of methods developed for the determination of triazine compounds in water, soil, crops, biological fluids, etc., have been reported in the literature, and several excellent reviews are available for the interested reader. " More method papers are published on the determination of triazines in water than for all other sample matrices combined (water > soil > crop). The majority of the water method reports relate to the determination of parent triazine compounds plus compounds from one or more other chemical classes of pesticides (e.g., phenoxy acids, carbamates, pheny-lureas, acetanilides, acetamides, organophosphorus compounds, etc.) for generalized multi-residue screening or monitoring purposes. Addressed in other more selective... 

The use of collision-induced dissociation (CID) and MS/MS techniques in conjunction with the API interfaces has dramatically impacted the fleld of environmental analysis. These techniques are now preferred for the determination of triazine compounds in water, soil, crops, etc., owing to the significant improvements in selectivity obtained via the monitoring of precursor-product ion pairs and increased sensitivity due to the reduction of chemical noise. 

Based on the results from radish seeds, we also studied the influence of the rue extract on germination of purslane. Purslane is a major weed worldwide of 45 crops in 81 countries. The ploughable layer of the soil cropped with maize contains about 220,000 purslane seed per m2. Purslane fruit is a capsule with a pyxidium and a caliptra containing 50-70 black seeds (Holm etal.,1977). 

Although technical chlordane is a mixture of compounds, two metabolites — heptachlor epoxide and oxychlordane — can kill birds when administered through the diet (Blus et al. 1983). These two metabolites originate from biological and physical breakdown of chlordanes in the environment, or from metabolism after ingestion. Heptachlor can result from breakdown of cis- and trans-chlordane, eventually oxidizing to heptachlor epoxide oxychlordane can result from the breakdown of heptachlor, m-chlordane, tra .s-chlordane, or fram-nonachlor (Blus et al. 1983). Heptachlor epoxide has been identified in soil, crops, and aquatic biota, but its presence is usually associated with the use of heptachlor, not technical chlordane — which also contains some heptachlor (NRCC 1975). Various components in technical chlordane may inhibit the formation of heptachlor epoxide or accelerate the decomposition of the epoxide, but the actual mechanisms are unclear (NRCC 1975). 

Overman AJ (1985) Off-season land management, soil solarization and fumigation for tomato. Soil Crop Sci Soc Fla Proc 44 35-39... 

Habib SA, Abdul-Rahman AA (1988) Evaluation of some weed extracts against field dodder on alfalfa (Medicago sativa). J Chem Ecol 14 443-452 Hao ZP, Wang Q, Christie P, Li XL (2006) Autotoxicity potential of soils cropped continuously with watermelon. Allelopathy J 18 111-119... 

Flutson, J.L. and Wagner, R.J. (1992) Leaching Estimation and Chemistry Model. A Process Based Model of Water and Solute Movement, transformation, Plant Uptake and Chemical Reactions in the Unsaturated Zone. Version 3. Dept, of Soil, Crop and Atmospheric Sciences, Series No. 92-3, Cornell University, Ithica, New York. 

Barak, J. D. and Liang, A. S. (2008). Role of soil, crop debris, and a plant pathogen in Salmonella enterica contamination of tomato plants. PLoS ONE 3, el657. 

Delfino J J, Miles CJ. 1985. Aerobic and anaerobic degradation of organiccontam inants in Florida groundwater. Soil Crop Sci Soc FI Proc 44 9-14. 

Kouwenhoven, J.K., Perdok, U.D., Boer, J. and Oomen, G.J.M. 2002. Soil management by shallow mouldboard ploughing in The Netherlands. Soil and Tillage Research 65 125-139. Liebman, M. and Davis, A.S. 2000. Integration of soil, crop, and weed management in low-... 

Note Crop. lisleJ in more (Ivan one category have a wide range of lnlcranec. depending upon sanation, in soils, crop vanelies. and crowing conditions. 

Fengthong, T., Dethoudom, S. and Keosavanh, O. (2002) Drinking water quality in the Lao People s Democratic Republic, in Seminar on the Environmental and Public Health Risks Due to Contamination of Soils, Crops, Surface and Groundwater from Urban, Industrial and Natural Sources in South East Asia, UN/ESCAP, Hanoi. 

Miglierina, A. M., and Rosell, R. A. (1995). Humus quantity and quality of an entic haplustoll under different soil-crop management systems. Commun. Soil Sci. Plant Anal. 26(19-20), 3343-3355. 

Figure 14.8. Thermograms for the volatilization of peptide-derived compounds in freeze-dried rhizodeposits leached from a soil cropped with maize after a daytime and a nighttime growth period and thermogram for the volatilization of L-glutamic acid. Reprinted from Leinweber, P., Jandl, G., Baum, C., Eckhardt, K.-U., and Kandeler, E. (2008). Stability and composition of soil organic matter control respiration and soil enzyme activities. Soil Biology and Biochemistry 40,1496-1505, with permission from Elsevier.

Tan, C.S., C.F. Drury, J.D. Gaynor, and T.W. Welacky (1993). Integrated soil, crop, and water management system to abate herbicide and nitrate contamination of the Great Lakes. Wat. Sci. Technol., 28 497-507. 

Tremblay, J., Beauchamp, C J. Split applications of supplementary N fertilizerfollowing incorporation of chipped ramical wood changes in selected biological and chemical properties of a soil cropped to potatoes. Can J... 

Knowledge of the relative role of vaporization in pesticide field dissipation has been markedly advanced by development of methods for measuring the vertical flux of vapors from a soil or soil-crop field plot. The basis and techniques for this method have been presented by Caro et al.(74) and Parmele et al. (7), and summarized recently by Taylor (6). The equation... 

Sandford, S. (1989) Crop residues/livestock relationships.- In Renard, C. et al. (eds) (1989) Soil, crop and water management systems for rainfed agriculture in the Sudano-Sahelian Zone.- Workshop proceedings. ICRISAT, Patancheru, India. 

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