Effects of spent mushroom substrate on soil physical conditions and plant growth in an intensive horticultural system

Abstract

A 2-year field trial determined the influence of applying spent mushroom substrate (SMS) on soil physical properties and the growth of 4 consecutive vegetable crops (sweetcorn, cabbage, potato, cabbage). Treatments comprised 0, 20, 40, and 80 t/ha of moist SMS, both with and without inorganic fertiliser, applied to each crop, giving a range of SMS rates up to 320 t/ha. SMS improved the environment for plant root growth by decreasing soil bulk density (by 0· 05-0·25 g/cm 3 at 100 mm depth), increasing aggregate stability (by 13-16%), reducing clod and surface crust formation (by 16-31 and 18-94%, respectively), increasing the infiltration rate (by 130-207 mm/h), increasing the water content of the soil (by 0-7% w/w), and reducing diurnal temperature changes. Some of these changes were not evident until repeated applications of 80 t/ha SMS had been made. Soil physical properties were related to crop yield, and soil physical properties’ principal components were related to crop principal components using regression analysis (r2 of 0·20-0·60 and 0·16-0·54, respectively). The soil physical properties that had the most influence on plant growth were specific to each crop and included bulk density, water content, surface crust cover, infiltration rate, and aggregate size distribution. Soil physical properties had a large influence on the potato yield irrespective of fertiliser use and on both cabbage crop yields when fertiliser was not used, but not on the sweetcorn yield (the first crop to be grown). The effect of changing soil physical properties on plant growth was most apparent when fertiliser was not used. This was because the improved physical properties increased plant yield (at least in part) because of increased plant nutrient uptake.

Physical properties of some intensively cultivated soils of Ireland amended with spent mushroom compost

“…The utilisation of SMC as a fertiliser has also received much attention and there is little doubt of its beneficial effect (Stewart et al, 1998). A number of authors including Wang et al (1984) and Kaddous and Morgans (1986) have noted the positive effects on soil physical properties brought about by the addition of SMC.…”

“…To-date many potential uses of SMC have been identified; these include its use as an ingredient in potting media (Maher and Magette, 1997), as a field amendment to vegetable crops (Kaddous and Morgans, 1986;Stewart et al, 1998) and as an amendment to grassland soils (Mullen and McMahon, 2001). The utilisation of SMC as a fertiliser has also received much attention and there is little doubt of its beneficial effect (Stewart et al, 1998).…”

High value crops in coarse-textured soil and nitrate leaching - How risky is it?

“…(1 compost (Gagnon et al 1998), and wetter soil and 50 to 250 kg m (3 reduction in BD with spent mushroom substrate on sandy loam (Stewart et al 1998). Reduced BD may not be an improvement for ginseng due to a detrimental effect on root shape (Roy et al 2008).…”

Comparison of Six Spent Mushroom Composts As Growing Media for Transplant Production of Lettuce

“…SMCs are used as compost for organic agriculture and horticulture (Ehaliotis et al 2005), soil amendments or potting soil Stewart et al 1998;Fermor et al 2000). These studies, however, only used one source of SMC at a time, and physical and chemical properties of various SMCs were not characterized.…”