Corn forage yield and quality for silage in short growing season areas of the canadian prairies
Citation
Guyader, J., Baron, V.S., Beauchemin, K.A. (2018). Corn forage yield and quality for silage in short growing season areas of the canadian prairies. Agronomy, [online] 8(9), http://dx.doi.org/10.3390/agronomy8090164
Plain language summary
Availability of short-season corn hybrids has made corn silage production possible in areas with shorter growing season. Consequently, corn silage production in Canada increased by 28% between 2011 and 2016, with the greatest increase in the Canadian prairies (+35% in Manitoba, +73% in Saskatchewan, and +52% in Alberta). Expansion of corn silage production is also due to its potential for high yield and digestibility and greater lodging resistance compared to small grains such as barley and oats. Given that beef and dairy cattle production are limited by digestible energy intake, corn silage represents an opportunity to increase meat and milk production without expanding land usage. However, corn grown on the Canadian prairies for silage does not always achieve its potential due to a cool environment where season-length and temperature limit kernel filling, maturation, and attainment of the required whole plant dry matter content necessary for ensiling. This study was conducted in collaboration with Dr. Vern Baron (Lacombe) and was aimed at determining biomass yield and nutritive quality of short-season corn hybrids. Six corn hybrids were grown in three years at four locations within the Canadian prairies with four field replications. Hybrids were harvested before occurrence of frost and analysed for nutrient content and in vitro digestibilities. This work showed the high variability of biomass yield and nutritive quality of short-season corn silage hybrids grown in Northern areas. The study showed that corn silage produced in cooler versus warmer locations contains less starch, but the fiber is more digestible. These differences in nutritive value may necessitate different diet formulations and perhaps corn growing strategies for these distinct types of corn hybrids.
Abstract
The development of short-season hybrids has made corn (Zea mays L.) silage (CS) production possible in cooler areas. This work aimed at determining biomass yield and nutritive quality of short-season corn CS hybrids. Six corn hybrids were grown in three years at four locations within the Canadian prairies with four field replications. Hybrids were harvested before occurrence of frost at a target dry matter (DM) content of 300 to 400 g kg−1. Corn heat units (CHU) from seeding to harvesting (CHUseed-harv) and water supply were recorded. Samples were analysed for nutrient content; i.e., DM, neutral detergent fiber (NDF), crude protein (CP), starch, and in vitro DM and NDF digestibilities (48 h incubation). Then, CHUseed-harv, water supply, whole plant DM, CHU rating of the hybrid, and cob percentage were assessed as predictors of nutrient content. Location, hybrid, and year affected nutrient composition and yield. Overall, CP and NDF were positively correlated (r = 0.48, p < 0.01), but both were negatively correlated with DM yield (r = −0.63, −0.28, p < 0.01) and starch (both r = 0.71, p < 0.01). Within and among locations, CHUseed-harv differently affected nutrient composition and DM yield. However, DM yield was the most predictable factor (R2 = 0.86) with CHUseed-harv being the strongest contributor (48%) to the overall variability, followed by water supply (23%). Whole plant DM and CHUseed-harv were also good predictors of starch (R2 = 0.54). This work showed the high variability of biomass yield and nutritive quality of short-season CS hybrids grown in Northern areas.