K3ERGZI7

2783

15 janvier 2021 10:05

15 janvier 2021 10:05

Kernza® intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & Dewey], the first perennial grain crop to come to market in North America, can provide a number of ecosystem services when integrated into cropping systems that are dominated by annual grain crops. However, grain yield from Kernza is lower than comparable annual cereal crops such as wheat and oats. Also, although Kernza is a long-lived perennial that can persist for decades, grain yield tends to decline over time as Kernza stands age leading most farmers to replant or rotate to a different crop after 3–5 yrs. Increased intraspecific competition as stand density increases with age has been reported to cause grain yield declines. We investigated the effect of strip-tillage applied at two different timings, between the third and fourth grain harvests, from a Kernza stand in upstate New York. Strip-tillage applied in late fall as plants were entering dormancy increased grain yield by 61% when compared to the control treatment without strip-tillage. However, total crop biomass was not reduced resulting in a greater harvest index for the fall strip-tillage treatment. Strip-tillage applied before stem elongation the following spring reduced overall tiller density and total crop biomass but did not impact tiller fertility or grain yield compared to the control treatment without strip-tillage. Increased grain yield in the fall strip-tillage treatment was due to an increase in the percentage of tillers that produced mature seedheads. This suggests that grain yield decline over time is at least partially caused by competition between tillers in dense stands. Results support further research and development of strip-tillage and other forms of managed disturbance as tools for maintaining Kernza grain yield over time.

None

• AB - Utile à l'AB
• FREDO biologie et travail du sol
• FREDO santé végétale
• céréale
• rendement

• crop management
• kernza intermediate wheatgrass
• perennial grain
• strip-tillage
• yield decline

Renewable Agriculture and Food Systems

1-7

01/12/2020

1 décembre 2020

10.1017/S1742170520000368 Le DOI est une URL unique de référencement d'une publication. Il est donc plus fiable et permanent qu'une URL classique

1742-1705, 1742-1713 L’ISSN est un code de 8 chiffres servant à identifier les journaux, revues, magazines, périodiques de toute nature et sur tous supports, papier comme électronique.