Suitability of Composts as Potting Media for Production of Organic Vegetable Transplants

Predicting Phytotoxicity of Compost-Amended Soil from Compost Stability Measurements

“…To measure the respiration of compost when amended in soils, food-waste compost-2, and green-waste compost were mixed with the soils at 0, 5, and 50% compost (v/v), where 0% provided a soil control and 5 and 50% represented field and horticulture applications (Clark and Cavigelli, 2005;Moldes et al, 2006), respectively. Six hundred milliliters of the mixtures were placed into heat seal bags (Kapak, Fisher Scientific, Pittsburgh, PA), aerated continuously with humidified air at 20 mL/min, and incubated at 20, 25, 30, 35, and 45°C to achieve different mineralization rates.…”

“…They are widely accepted, can measure the compounded effects of various phytotoxic factors, and have been suggested to be the ultimate maturity index to which other methods should be compared (Chen and Inbar, 1993;Epstein, 1997, Zucconi et al, 1981Wu et al, 2000;Cooperband et al, 2003;Emino and Warman, 2004). However, they vary greatly in methodology, and can be inconsistent, insensitive, and time-consuming (Warman, 1999;Cooperband et al, 2003;Rynk, 2003;Emino and Warman, 2004;Thompson, 2004). Furthermore, their utility is dependent on species sensitivity (Epstein, 1997;Emino and Warman, 2004).…”

“…However, they vary greatly in methodology, and can be inconsistent, insensitive, and time-consuming (Warman, 1999;Cooperband et al, 2003;Rynk, 2003;Emino and Warman, 2004;Thompson, 2004). Furthermore, their utility is dependent on species sensitivity (Epstein, 1997;Emino and Warman, 2004). For these reasons there is little consensus on the ideal plant assay to evaluate composts.…”

“…Stability is typically determined by respiration; however, there is currently no universal method for measuring maturity (Iannotti et al, 1994;Paletski and Young, 1995;Epstein, 1997;Gariglio et al, 2002;Adani et al, 2003;Cooperband et al, 2003;Rynk, 2003;Benito et al, 2005aBenito et al, , 2005bGoyal et al, 2005). Respiration is measured by either laboratory tests or quick and inexpensive methods such as the Solvita ® Test or using oxitop (Brewer andSullivan, 2003, Rynk, 2003;Iranzo et al, 2004), and is a fairly routine measurement.…”

Assessing Maturity of Rotary Barrel Green Waste Composts for Use as Tomato and Sweet Pepper Seedling Starter and Transplant Growth Substrates

“…The use of peat alternatives including compost produced from various organic materials is promising (Clark and Cavigelli, 2005;Ghanbari Jahromi and Aboutalebi, 2011;Ribeiro et al, 2007;Schroeder and Sell, 2007). However, several problems may result from the use of compost as a substrate or substrate component.…”