Cropping history

Anderson JPE, Domsch KH (1978) A physiological method for the quantitative measurement of microbial biomass in soils. Soil Biol Biochem 10 215-221 Anderson TH, Domsch KH (1990) Application of eco-physiological quotients (qC02 and qD) on microbial biomasses from soils of different cropping histories. Soil Biol Biochem 22 251-255... 

Watts, C.W., Whalley, W.R., Longstaff, D.J., White, R.P., Brooke, P.C and Whitmore, A.P. 2001. Aggregation of a soil with different cropping histories following the addition of organic materials. Soil Use and Management Y7 263-268. 

The species composition and density of weed seed in soil vary greatly and are closely linked to the cropping history of the land and the farming practices. Soil seedbank size may include up to a million seeds/m2 (Fenner, 1985). 

Specific management practices influence triazine runoff and leaching, including fertilizer type, tillage crop residues, and previous crop history, as well as triazine application, formulation, and placement (Baker and Mickelson, 1994). Tillage systems affect various soil properties, such as soil moisture, temperature, pH, organic matter, water flow, and microbial populations, especially at and near the soil surface. These factors can affect transformation, retention, and transport of herbicides in soil. Interactions of and compensations between these processes can influence our prediction of triazine transport in soil. Therefore, triazine movement is usually studied under one management practice at a time. 

Field Evaluation of Chemical Rotations. During 1985-1988, experiments were conducted at the Univ. of 111. Northwest Illinois Agricultural Research and Development Center near Monmouth, Illinois. A single 2-acre field was used over the 4 years of research. The soil was a Muscatine silt loam and the slope was 2% (soil 69, Table I). The cropping history prior to 1985 was soybeans, 1980-82 wheat, 1983 corn, 1984. No soil insecticide had been used for at least three years prior to 1985. Chlorpyrifos (Lorsban 4E) was used for adult corn rootworm control during 1984. 

Haynes, R. J. (20()0). Interactions between soil organic matter status, cropping history, method of ciuantilication and sample pretreatmenl and theii- effects on measured aggregate stability. Biol. Fertil. Soils 30, 270-275. 

Adjacent fields having the same soil but different fertilization and cropping histories develop different levels of soil fertility over time. This fertility level greatly affects the crop response to particular nutrients and obvi-... 

During the annual inspection, input and output records as well as accounts have to be available. Crop records required include treatments applied for the last three years for land in-conversion crop rotation plans and cropping areas cropping history including yields application of farmyard manures and other... 

Site information, including a description of the plot size, control areas, buffer zones, etc. The test site selection process which is based on factors such as pesticide use history, crop history, soil type, precipitation and irrigation history, generally precedes protocol approval ... 

Pesticides used on crops grown on the test site in previous seasons may also have an impact on the outcome of a field residue trial. Carryover of prior pesticide applications could contaminate samples in a new trial, complicate the growth of the crop in a trial, or cause interference with procedures in the analytical laboratory. For this reason, an accurate history of what has transpired at the potential test site must be obtained before the trial is actually installed. The protocol should identify any chemicals of concern. If questions arise when the history is obtained, they should be reviewed with the Study Director prior to proceeding with the test site. In most annual crop trials, this will not be a significant issue owing to crop rotations in the normal production practices, because the use of short residual pesticides and different chemical classes is often required for each respective crop in the rotation. However, in many perennial crops (tree, vines, alfalfa, etc.) and monoculture row crops (cotton, sugarcane, etc.), the crop pesticide history will play a significant role in trial site selection. 

A description of the trial area, which includes a layout of the plots, the previous history of the trial area, a description of the plots, special local features, and the ownership of the land, should be recorded. Increasingly, digital photography is used to document site location, type of application used, crop growth stage, etc. 

Access to crop and chemical application history should be made available if possible. Several large cooperators in Latin America consider this information confidential, however. 

Field studies in at least two paddies where the sediment has different characteristics of pH, texture and organic carbon contents are required for registration purposes. Since especially clay content and organic carbon content affect the agrochemical behavior in sediments, it is desirable that both systems have widely different characteristics with respect to these two criteria. These paddies should have cultivation history records on type of crop, variety, and agrochemical applications for at least 5 years. 

The study of allelopathy has a long history. According to Rice (j>), Lee and Monsi (6 ) found a report by Banzan Kumazawa in a Japanese document sane 300 years old that rain or dew washing the leaves of red pine (Pinus densiflora) was harmful to crops growing under the pine. This was substantiated by these workers (6j in a series of experiments. Historically, this is considered to be the first report on allelopathy. 

Surveys of mycotoxin contamination levels in organic and conventional crops often give conflicting results and will therefore not be described in detail here. They often poorly describe the management history of samples included in the survey and may therefore be misleading with respect to the causes of differential mycotoxin loads. Also, the contribution made by primary production practices/factors and storage conditions to overall mycotoxin loads were unclear for most of these studies. 

Hevea rubber is undoubtedly one of the unique crops of history and of all agriculture, and one of the most interesting. It is not easy to produce rubber. Research is the tool by which it is possible to grow vast acreages of the tree as a profitable crop. This could never have been done without the past /and present intensive investigations of careful scientists over more than 30 years. Repeated reference in the literature indicates that diseases are the limiting factors in natural rubber production, and that planters owe a debt to disease-control workers. 

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