Beneficial Microorganisms in Low-Input Agriculture

The overall involvement of microorganisms in crop production still remains much of a mystery. Because of their distribution and size, most studies have been done in the laboratory and the implications of these studies referred back to the field. With this approach, unfortunately, much remains unknown, not only about the growth of individual organisms, but certainly the interactions of organisms in nature. Several nontraditional soil amendments have been marketed over the years that capitalize on our lack of understanding of soil microbial processes. Terms such as soil activators, soil enhancers, and enzyme stimulators have been used, claiming to improve soil structure, the life of the soil, reduce soil erosion, release pent up nutrients (one of my favorites), and others claims. Often the product is based on revolutionary new research that has yet to be tested by the local land-grand university. From my perception, more often than not, an idea is being sold rather than a viable product. Those of us in science, nevertheless, know there are happenings occurring in nature that we don\u27t adequately understand, and some chance discovery of one of these products may have scientific merit. But until it is thoroughly tested by independent researchers not tied to the product, one should be very cautious of product claims

Nitrogen conservation in swine manure composting land-application systems

The use of bedding in the popular hooped houses for swine production generates large volumes of manure that composts easily. However, composting results in nutrient losses, especially for nitrogen, which then diminish its value as a fertilizer. This study looks at carbon and nitrogen dynamics in the composting process and subsequent soil mineralization

Optimizing microbial associations to enhance N and P soil nutrient availability

Sustainable farming systems rely in part on recycling nutrients through materials such as crop residues, manure, or biological inputs. Three nutrients commonly added as fertilizers in agricultural production systems are nitrogen (N), phosphorus (P), and potassium (K). Past research has shown that fungal and bacterial microbial systems may be an important way to add nutrients to the soil or to enhance availability of those nutrients already present. But the interaction of beneficial fungi and bacteria in a synergistic relationship with higher plants is still poorly understood. Moreover, very little is known about the ecology of these beneficial soil fungi

Integrated soil and weed management production systems for perennial food crops

Several alternative weed management tactics for strawberry and grape production were tested for their effects on weed control, crop yield and soil quality enhancement

Reducing pesticide use in Iowa vineyards: Alternatives to herbicides for vineyard weed management

Mulches can play a role in vineyard management. This project explored the optimum uses and practices for applying various mulches to grape agroecosystems

Evaluation of the impact of tillage/cropping systems on soil microflora and week seedbank predation

Soil erosion and pesticide use are critical issues in sustainable agriculture. With a view to decreasing the amount of pesticides used for weed control, researchers assessed the impact of tillage, cropping systems and weed management regimes on seasonal and long-term weed and weed seedbank population dynamics, especially in Conservation Reserve Program land being returned to production

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ABSTRACT The living component of soil is difficult for students to learn about and understand because students have difficulty relating to things they cannot see (beyond sight, beyond mind). Line drawings from textbooks help explain conceptual relationships but do little to stimulate an active interest in the living component of soil. Alternatively, movies, videotapes, or more recently web-based videos show motion of the organisms but the environment is artificial compared with direct observations on a soil the student has collected. Inexpensive, easy-to-prepare media dishes can be used for growing organisms from soil brought into the classroom by the student. The techniques described in this article are relatively simple and require little expertise to grow the organisms. An inexpensive microscope (ideally up to 500× magnification but acceptable to 100× magnification) and light source are needed but an autoclave and aseptic conditions are not required. The organisms are grown in mixed culture in petri dishes on lowenergy medium. Although bacteria grow prolifically on the dishes, their small size makes individual organisms hard to see at 500× but they serve as a major food source for larger organisms that can be observed. Different organisms will develop based on dish moisture. Wetter conditions encourage protozoa and rotifer growth, whereas drier soil conditions favor fungi, nematodes, and springtails. With several dishes at different moistures, fungi, protozoa, mites, springtails, nematodes, rotifers, potworms, and perhaps a nematode-trapping fungus or tardigrada can be commonly observed. Web resources should be used to provide beginning students with high quality images and video to confirm observations from the culture dishes