Potential of winter double crops and tillage for managing manure-based nutrient loading

AimsIntensive dairy regions have an opportunity to enhance recycling of manure nutrients within forage rotations improving the system sustainability. This study investigated the combined effect of winter double crops and tillage on nutrient uptake, yield, and forage quality under annual manure applications with silage corn (Zea mays).MethodsThe 2 x 4 split block study consisted of conventional (CT) vs minimal (MT) tillage, and combinations of manure (M) vs synthetic fertilizer (S) and winter triticale (x Triticosecale) (D) vs fallow (F) for each tillage type. Plant tissue was collected for annual forage yield, nutrient concentrations, and forge quality.ResultsIn soils, M significantly increased SOC, TN, Olsen P, K, Na, and Zn (20-96%) along with multiple enzyme activities (45-75%) and decreased NH4-N and Ca (9-26%) compared to synthetic fertilizers, regardless of tillage and winter crop. Manure increased tissue N, P, and K for both corn silage (12-39%) and triticale (31-45%) regardless of tillage. However, tillage effects were seen for corn Na and triticale Mg, Na, Zn, Ca, and Mn. Triticale removal of all nutrients was significantly greater with manure application (77- 97%) regardless of tillage. While inclusion of winter double crop removed 1.1 - 1.8 times as much NPK as winter fallow, triticale tissue K exceeded maximum concentrations for feed forages. Manure increased crude protein for both forages; however, M also increased triticale fiber content and reduced feed energy compared to synthetic fertilizer.ConclusionWinter triticale can increase forage production and enhance manure nutrient utilization in forage rotations.

Automated summary

This study investigated the combined effect of winter double crops and tillage on nutrient uptake, yield, and forage quality, and found that winter double crops can increase forage production and enhance nutrient utilization.