Effect of green manure and supplemental fertility amendments on selected soil quality parameters in an organic potato rotation in Eastern Canada

Soil quality response to cover crops and amendments in a vineyard in Nova Scotia, Canada

“…The range of MBC following amendment applications was similar to that reported by Nair and Ngouajio (2012) in a 3-year organic vegetable production system with cover crops and compost at Michigan State University. The qMBC followed a similar trend as MBC among the fertility treatments which is consistent with findings of Sharifi et al (2014). The high MBC and qMBC following addition of MSFW was consistent with other studies (Crecchio et al, 2004;Sharifi et al, 2014).…”

“…Nitrogen as NH 4 NO 3 (34% N) and sulfur as MgSO 4 (7H 2 O) (90% S) were applied at rate 40 kg ha −1 in the WA treatment. The MSFW was applied at 13.4 Mg ha −1 on a dry weight basis based on the assumption that 15% of the total N is available in the application year (Sharifi et al, 2014). Nitrogen was applied at rate 30 kg ha −1 and K was applied as KCl (62% K) at rate 83 kg ha −1 to balance the nutrients in the MSFW.…”

Legumes can reduce economic optimum nitrogen rates and increase yields in a wheat–canola cropping sequence in western Canada

“…In this study, the green manure was killed off in the summer months, thus providing a period where soil moisture was not being consumed and where mineralization of the N-rich residues could occur without crop uptake. Early killing and incorporation of green manure crops may increase the risk of N losses through leaching and denitrification, particularly in areas with high precipitation like Eastern and Atlantic Canada (Zebarth et al, 2003;Sharifi et al, 2014). Under the relatively dry conditions of the Canadian prairies, where soils are frozen from November to April, the probability of N losses through leaching and denitrification are reduced compared to more humid environments .…”

Dry matter accumulation and potato productivity with green manure

“…Green manure improves the physical, chemical and biological properties of soil (Sharifi et al, 2014) including water retention, cation exchange capacity and microbial activity (Riutta et al, 2012;Dash et al, 2014). In addition, green manure reduces weed incidence and soil pathogens by increasing beneficial microorganisms, as well as controlling disease-causing pathogens in potato (Davis et al, 2010, Larkin et al, 2010, Himmelstein et al, 2014.…”

“…This may reduce or replace conventional chemical fertilizers in production systems, especially by releasing N in organic production systems (Ferreira et al, 2013). In addition, green manure can supply other nutrients and promote beneficial effects in physical, chemical and biological soil properties (Sharifi et al, 2014).…”