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Increasing crop diversity mitigates weather variations and improves yield stability.

Gaudin AC, Tolhurst TN, Ker AP, Janovicek K, Tortora C, Martin RC, Deen W - PLoS ONE (2015)

Bottom Line: Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses.Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa.Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental stresses.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON, N1G2W1, Canada.

ABSTRACT
Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental stresses. This could help to sustain future yield levels in challenging production environments.

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Benefits of diversification under different weather scenarios.(A-B) Corn yields compared to CCSS rotation (%) obtained for selected cluster in (A) reduced tillage and (B) tilled systems. (C-D) Soybean yields compared to CCSS rotation (%) obtained for selected clusters in (C) reduced tillage and (D) tilled systems. Crop abbreviation: C = corn, S = Soybean, O = Oat, B = spring barley, W = Winter wheat, rc = underseeded red clover, A = Alfalfa. (*) significantly different from high yielding years (cluster E) at p = 0.05.
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pone.0113261.g003: Benefits of diversification under different weather scenarios.(A-B) Corn yields compared to CCSS rotation (%) obtained for selected cluster in (A) reduced tillage and (B) tilled systems. (C-D) Soybean yields compared to CCSS rotation (%) obtained for selected clusters in (C) reduced tillage and (D) tilled systems. Crop abbreviation: C = corn, S = Soybean, O = Oat, B = spring barley, W = Winter wheat, rc = underseeded red clover, A = Alfalfa. (*) significantly different from high yielding years (cluster E) at p = 0.05.

Mentions: Year cluster D (n = 10) and A (n = 7) grouped the hottest and driest years for corn and soybean respectively (S3, S4 Figs.). Growing seasons were short with significant water deficit and high temperatures during reproductive growth stages, resulting in significantly lower yields than in high yielding years (Cluster E) (S3, S4 Figs., Table 3). Corn yield under all diversification strategies in reduced tillage was increased compared to CCSS rotations when hot and dry conditions occurred (Fig. 3A, S5 Fig.). Benefits of diversification were higher than those observed under favorable conditions. Introducing oat and barley with red clover or alfalfa was particularly beneficial to mitigate droughty conditions (+734 kg ha-1 on average, S5 Fig., Fig. 3A). In tilled systems, all rotations but CCSW had higher corn yield than CCSS in dry and hot years (S5 Fig.), the highest yield benefits being obtained from alfalfa in rotation (+8.7% Fig. 3B).


Increasing crop diversity mitigates weather variations and improves yield stability.

Gaudin AC, Tolhurst TN, Ker AP, Janovicek K, Tortora C, Martin RC, Deen W - PLoS ONE (2015)

Benefits of diversification under different weather scenarios.(A-B) Corn yields compared to CCSS rotation (%) obtained for selected cluster in (A) reduced tillage and (B) tilled systems. (C-D) Soybean yields compared to CCSS rotation (%) obtained for selected clusters in (C) reduced tillage and (D) tilled systems. Crop abbreviation: C = corn, S = Soybean, O = Oat, B = spring barley, W = Winter wheat, rc = underseeded red clover, A = Alfalfa. (*) significantly different from high yielding years (cluster E) at p = 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4320064&req=5

pone.0113261.g003: Benefits of diversification under different weather scenarios.(A-B) Corn yields compared to CCSS rotation (%) obtained for selected cluster in (A) reduced tillage and (B) tilled systems. (C-D) Soybean yields compared to CCSS rotation (%) obtained for selected clusters in (C) reduced tillage and (D) tilled systems. Crop abbreviation: C = corn, S = Soybean, O = Oat, B = spring barley, W = Winter wheat, rc = underseeded red clover, A = Alfalfa. (*) significantly different from high yielding years (cluster E) at p = 0.05.
Mentions: Year cluster D (n = 10) and A (n = 7) grouped the hottest and driest years for corn and soybean respectively (S3, S4 Figs.). Growing seasons were short with significant water deficit and high temperatures during reproductive growth stages, resulting in significantly lower yields than in high yielding years (Cluster E) (S3, S4 Figs., Table 3). Corn yield under all diversification strategies in reduced tillage was increased compared to CCSS rotations when hot and dry conditions occurred (Fig. 3A, S5 Fig.). Benefits of diversification were higher than those observed under favorable conditions. Introducing oat and barley with red clover or alfalfa was particularly beneficial to mitigate droughty conditions (+734 kg ha-1 on average, S5 Fig., Fig. 3A). In tilled systems, all rotations but CCSW had higher corn yield than CCSS in dry and hot years (S5 Fig.), the highest yield benefits being obtained from alfalfa in rotation (+8.7% Fig. 3B).

Bottom Line: Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses.Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa.Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental stresses.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON, N1G2W1, Canada.

ABSTRACT
Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental stresses. This could help to sustain future yield levels in challenging production environments.

Show MeSH
Related in: MedlinePlus