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CURRENT RESEARCH

Compost Science & Utilization, (2008), Vol. 16, No. 3, 142

Materials and Methods

Composting To Eradicate Fusarium Graminearum From Infested Livestock Feed
Investigators: Francis J. Larney, Agriculture and Agri-Food Canada, Research Centre, Lethbridge, Alberta, Canada; T. Kelly Turkington, Agriculture and Agri-Food Canada, Research Centre, Lacombe, Alberta, Canada

Objectives: Fusarium head blight, caused by Fusarium graminearum, could potentially become a major concern for Alberta's cereal industry. Infested feed grain in feedlot manure may act as a means of spreading the disease when manure is land-applied. The ability of manure composting to eradicate the pathogen on infested grain (wheat, barley, corn) was evaluated. F. graminearum was rapidly eradicated from infested grains buried in compost windrows with no recovery after 2 d where windrow temperature attained 51°C. Composting represents an effective strategy in mitigating the dissemination of F. graminearum via manure should land application occur on fields that are subsequently used for cereal or corn production.

Soil Improvement

Nutrient Mineralization And Loss In Composts Made From Wheat Straw And Effects On Musk Melon Quality
Investigators: Jianming Li, Zhirong Zou, College of Horticulture, Northwest A&F University, Shaanxi Province, China; M.H.Behboudian, Allan Morton, Institute of Natural Resources, Massey University, Palmerston North, New Zealand; Zhonghong Wang, Tibetan Agricultural and Animal Husbandry College, Tibetan Autonomous Region, China; and Jie Gud, College of Natural Resource and Environment, Northwest A&F University, Shaanxi Province, China
Objectives: To study variability in the nutritional quality of organic composts and its effects on produce quality and utilization of marginal desert lands. For this experiment eight combinations of two compost types mixed in different proportions of sandy soil were used to grow musk melon (Cucumis melon L.). The two types of composts were cattle manure with straw (CS) and sheep manure with straw (SS). The total content and loss of N, P, and K increased with the ratio of compost added to the substrate, and was higher in SS substrates than in CS substrates of equivalent compost:soil ratios. The mineralization of N, P and K increased with more compost in the substrates. The mineralization rate of N and P in CS substrates was higher than that in SS substrates, while the reverse was the case for K. The yield and quality of fruit was higher in CS than in SS substrates. The nitrate content of the fruit tended to decline as more compost was added to the substrates. It was concluded that CS substrates were better than SS substrates and the optimum rate of addition was a 1:1 ratio of compost and sandy soil.

Microbial Response To The Application Of Amendments In A Soil Contaminated With Trace Elements
Investigators: Branzini A and MS Zubillaga, Cátedra de Fertilidad y Fertilizantes, Facultad de Agronomía, Universidad de Buenos Aires., Buenos Aires, Argentina; Liet OJM, ENSAT, Toulouse, France
Objectives: The aim of this study was to evaluate the effects of the application of two organic amendments (biosolids and equine compost) on soil microbial activity, in a soil contaminated with copper (Cu), zinc (Zn) and chromium (Cr).
The results showed that at the end of the incubation period, as much in contaminated soils as in soils without contamination, the application of organic amendments increased significantly (p=0.0062 and p=0.0005, respectively) the total activity of microorganisms. The application of both composts to slightly acid soils increased the initial and final values of pH, though without variation of the range of soils lightly acid. There was no evidence of modification in electrical conductivity (EC) because of the incorporation of compost. At the end of the incubation period a negative relation was observed among EC and CO2-C (R2 = 0.74, p = 0.0028). It might be expected that the amendments application and their effect on trace elements bioavailability, restores soil microorganisms activity.

Enhanced Stabilization of Home-kitchen Waste by Hydrophilic Porous Media for Organic Cultivation
Investigators: Hsiao-Dao Chang, Department of Environment and Safety Health Engineering, Ming-Chi Technology University, Tai-Shan, Taipei, Taiwan; Chao-Ying Chen Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
Objectives: To show the importance of maintaining humidity and microbial activity of solid state fermentation, hydrophilic porous media were prepared and surveyed in this study. The amending of porous media resulted in a thriving of thermophile microbes; in addition, high hydrophilic and charge form, and high fermentation temperature were observed. Another biotic activity index -adenosine dinuceotide triphosphate was analyzed, the result revealed that biomass was better entrapped into the porous media as compared to the simple cellulosic materials. When porous media were incorporated into the compost formula, they caused an increase in composting activity. The porous media high in hydrophilic and charged ingredient increased microbe activity. Stability of compost for organic cultivation was tested on vegetables grown in a ventilated screen house. A strong correlation existed between compost stability and crop production. Moreover, stabilized compost was able to reduce disease severity. Incidences of Sclerotinia rot, Alternaria leaf spot, Erwinia rot and the root-knot nematode, common in wet and shielded areas of organic cultivation, were decreased when stabilized compost was utilized.