IMPACT OF USING LEACHED SPENT MUSHROOM COMPOST AS A PARTIAL GROWING MEDIA FOR HORTICULTURAL PLANTS

More than 10 million metric tons of spent mushroom compost (SMC), which is a by-product of Agaricus bisporus mushroom, is produced in the world. Adding the compost to the soil resulted in improving the nutritional status of the plants. This study aims experiment is to study the effect of SMC on cucumber plant growth. A basic property of SMC and high concentrations of soluble salts restricted its implementation in the agricultural arena. The SMC was leached in order to reduce its salinity. Leached spent mushroom compost has less salinity while carbon and nitrogen content as well as inorganic cation components did not change significantly when compared to non-leached SMC. To study the effects of SMC on plant growth, leached SMC in rates of 15, 25, 35, and 45% were added to a sandy-loam soil medium. Cucumber plant growth rate was evaluated based on fruit number and plant height. Results showed that additions of 15% and 25% leached SMC to growing media significantly improved the cucumber plants growth.     

ADDITION OF PULP MILL ASH RAISES PH,MODIFIES PHYSICAL PROPERTIES,AND ALTERS YOUNG TOMATO PLANT GROWTH AND MINERAL NUTRITION IN A PEAT-BASED SUBSTRATE

Pulp and paper mills often burn wood waste to fuel their boilers. The ash from a Mississippi pulp mill boiler was evaluated for potential use as an amendment to peat moss-based greenhouse substrates for production of young tomato plants. Between 0 and 50% ash was added to a custom-blended peat moss-based substrate, and these were compared to a commercially available substrate without ash. Addition of ash increased substrate pH, conductivity (EC), bulk density and water holding capacity, while reducing airspace and average particle size. In general, tomato plants grown in 0–40% ash had similar growth indexes as plants grown in commercial substrate. Increasing amounts of ash decreased tomato shoot nitrogen (N), potassium (K), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentration, and increased concentrations of phosphorus (P), calcium (Ca), sulfur (S), and boron (B). These results indicate that pulp mill ash has the potential to be used as a substrate component for greenhouse container production of tomato.