Agronomic crops

R. M. Sacher, "Strategies to Discover Plant Growth Regulators for Agronomic Crops," in Chemical Manipulation of Crop Growth and Development 1982, p. 167. 

However, climate, season, and cropping system specificity still represent serious limits for a further diffusion of soil solarization practice, as effective results are mostly provided by summer application to specific cropping systems, i.e., greenhouse and field horticulture and fruit orchards, in warm climates. Adversely, solarization is less effective and more expensive in cooler regions and not suitable for rain-fed agronomic crops in large areas. 

Eckert, D.J. and McLean, E.O. (1981) Basic cation saturation ratios as a basis for fertilizing and liming agronomic crops I. Growth chamber studies. Agronomy Journal 73, 795-799. 

They include a reduction of hand tillage costs. Before herbicides, hand hoeing was regularly practiced in all vegetable crops and in most agronomic crops. 

Our appreciation of the magnitude and, in fact, the presence of air pollution problem on vegetation is rooted in our understanding of the acute responses of plants to toxicants. While this approach deals with only our initial appraisal of the problem, it has been a valuable tool and an important first step in understanding the dosimetry of toxic response in plants. O. Clifton Taylor discusses the variety of acute responses exhibited on a number of horticultural and agronomic crops. 

Figure 22. Theoretical graph of the genetic yield potential of an agronomic crop compared to actual yield after losses due to environmental and biological stresses.

Potassium is the third most important fertilizer element, in terms of amounts added as fertilizer, after nitrogen and phosphorus. Many soils of humid and temperate regions are unable to supply sufficient K+ for agronomic crops. Farmers in these areas long ago recognized the benefits of applying wood ash and other liming materials to their acid soils. Both the alkalinity of the ash (to counter Al3+ toxicity) and its K and Ca content are beneficial. 

Jones, J. B., Jr. (1967). Interpretation of plant analysis for several agronomic crops. In Soil Testing and Plant Analyses, ed. G. W. Hardy et al., pp. 49-58. Madison, WI Soil Science Society of America. 

Typically, phosphorus is added in various forms to a watershed (Figure 9.1). These include fertilizers, nonhazardous wastes (animal manures and biosolids), and nutrient-enriched waters. Historically, organic wastes such as animal manures were applied to agronomic crops and pastures on the basis of the nitrogen availability, which has resulted in excessive application of phosphorus. As a result, many uplands used for land application of wastes have accumulated phosphorus in excess amounts. A major portion of the phosphorus added to uplands is retained within the soil. However, as upland soils become saturated or overloaded with phosphorus, a significant portion of the stored phosphorus can be released and transported with water during runoff events. 

Barber, S.A., t995. Soil Nutrient Bioavailabitity A Mechanistic Approach. Wiley, New York. Barber, S.A., Cushman, J.H., 1981. Nitrogen uptake model for agronomic crops. In Inskandar, I.K. (Ed.), Modeling Wastewater Renovation-Land Treatment. Wiley-lnterscience, New York, pp. 382-A09. 

Through the use of chemical technology, large increases have been reported in recent decades in the production of agronomic crops in the United States (5). New herbicides, fungicides, insecticides, and fertilizers have been developed and applied on a broad scale on farms and orchards. Recently, however, widespread fears have developed concerning possible air and water pollution and the contamination of fruits and vegetables with toxins. 

Geotextiles have a large variety of uses. These can be used for mulch around newly planted seedlings (Figure 7.9). The mats provide the benefits of natural mulch in addition, controlled-release fertilizers, repellents, insecticides, and herbicides can be added to the mats as needed. Research results on the combination of mulch and pesticides in agronomic crops have been promising. 

The fastest growing group of insecticides introduced to the market since the launch of pyrethroids (3), with wide-spread use in most coimtries in many agronomic cropping systems especially against sucking pests, but also against ectoparasitic insects. 

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