Value of integrating perennial forage seed crops in annual cropping sequences

Abstract

Integrating Perennial Forage Seed Crops in RotationsCore Ideas  Integration of perennial forage seed crops in cropping sequences can be productive and profitable. Prevailing commodity prices have bearing on the relative profitability of the crops. Forage legumes can replace external nitrogen application for two succeeding crops. Complementary studies help to elucidate agro-ecosystem services of perennial seed crops.

Integration of perennial forage seed crops for cropping systems resiliency in the Peace River region of western Canada

“…The cumulative returns of different 4-year cropping sequences were assessed in terms of canola equivalent yield (price ratio of non-canola to canola multiplied with the yield of canola crop) and gross margins. The creeping red fescuebased sequences had higher canola equivalent yield and gross margins compared to the annual crops-based sequences (Khanal et al 2021).…”

“…In a recent study conducted at Beaverlodge in the Peace River region, an unfertilized wheat crop preceded by a biennial stand of red clover or alsike clover produced yield increases of up to 45% compared to wheat crop preceded by 2 years' sequences of annual crops. Similarly, canola after the wheat crop preceded by clovers in the sequence yielded 40%-70% higher than those from annual crop sequences (Khanal et al 2021). However, the transition from perennial grass seed crops to annual crops under a no-tillage system may not have a break-crop advantage for the immediate following crop (Khanal et al 2021) due to a high carbon-to-nitrogen ratio (C:N) causing slow decomposition of grass residues and root materials (Livesley et al 2016).…”

“…Similarly, canola after the wheat crop preceded by clovers in the sequence yielded 40%-70% higher than those from annual crop sequences (Khanal et al 2021). However, the transition from perennial grass seed crops to annual crops under a no-tillage system may not have a break-crop advantage for the immediate following crop (Khanal et al 2021) due to a high carbon-to-nitrogen ratio (C:N) causing slow decomposition of grass residues and root materials (Livesley et al 2016). However, perennial forage crops with nearly four-times higher root-to-shoot ratio relative to annual crops (Bolinder et al 2007;Thiagarajan et al 2018) can increase soil carbon stock under crop rotation leading to improvement in soil health in the long run (Dheri et al 2022).…”

“…Without supplemental nitrogen, barley grain crops following hay crops of alfalfa, birdsfoot trefoil, alsike clover, red clover, and sweet clover had significantly higher yields than barley following fallow on Gray Luvisolic soils (Hoyt and Leitch 1983). A recent study by Khanal et al (2021) showed that the biennial legume seed crops of red and alsike clovers could replace nitrogen fertilizer requirements for succeeding sequential wheat and canola crops by at least 90 and 45 kg ha −1 , respectively (Khanal et al 2021). With proper planning of cropping sequences, perennial legume seed crops can enhance the nitrogen economy of the cropping systems.…”

Agroecological Approach to Agricultural Sustainability, Food Sovereignty And Endogenous Circular Economy

“…It may include various tillage systems such as conservation tillage, strategic or occasional tillage, bio-tillage, cover cropping, residue management, green manuring, organic amendments, biochar, biofertilizers and supplemental nutrient applications in the right forms, at right time, at the right rates and with right methods. Under favourable environmental conditions, annual legume crops can fix up to 260 kg atmospheric nitrogen per ha (equivalent to 565 kg Urea fertilizer) (Herridge et al, 2022), and preceding legumes crops can meet full nitrogen requirement for the immediate succeeding crop and up to 50% nitrogen requirement for the second succeeding crop (N. Khanal, 2022;N. Khanal et al, 2021).…”