Divergent response of hay and grain yield of oat: effects of environmental factors and sowing rate.

BACKGROUND: Oat (Avena sativa L.) is recognized for its impressive productivity in marginal environments, and the sowing rate is an important crop management practice that potentially enhances oat productivity. Previous studies have reported the effect of sowing rate on oat yield; however, the results from such studies are inconsistent. Thus, based on 43 studies across eight countries, this study aimed to assess changes in hay and grain yields in response to sowing rate and, in combination with a boosted regression tree, to evaluate and rank the dominant factors (e.g. climate conditions, soil conditions, and sowing rate) affecting changes in hay and grain yields of oat. RESULTS: The results revealed that increasing the sowing rate significantly increased the response ratio of grain yields and hay yields by averages of 7.3% and 7.9% respectively. However, the response ratios of grain yields and hay yields in response to changes in sowing rate were affected by different factors. Climate condition and mean annual precipitation primarily affected the response ratios of hay yields, whereas the sowing rate dominated changes in the response ratios of grain yields, with the response ratios of grain yields peaking at a sowing rate of 85 kg ha-1 . CONCLUSION: Optimizing the sowing rate with site-specific environmental conditions could be a potential strategy for profitable oat production, given that oat can be produced under marginal environments (e.g. cool-wet climates and soil with low fertility). © 2022 Society of Chemical Industry.