Factors Affecting Mixed Planting Success in Farmers' Fields

Jim Crocker
13th July, 2024

Factors Affecting Mixed Planting Success in Farmers' Fields

Across a network of farms in Western Switzerland (c), this study assessed the variability of intercropping winter oilseed rape (Brassica napus) with diverse service plant mixtures, such as those without (a) and with (b) buckwheat (Fagopyrum esculentum), a key driver of service plant biomass.

Image adapted from: Bousselin et al. / CC BY (Source)

Key Findings

  • In Switzerland, intercropping winter oilseed rape (WOSR) with service plants showed inconsistent crop yields
  • The main factors affecting service plant growth were the specific plant mixture composition and precipitation levels
  • Insect pest damage in spring, due to minimal insecticide use, was the primary reason for low WOSR yields in most fields
The intercropping of winter oilseed rape (WOSR) with frost-sensitive service plants is gaining popularity among farmers in Western Europe due to its potential benefits, including weed control and nitrogen (N) supply. However, in Switzerland, this practice has shown inconsistent results in terms of crop yields. A recent study conducted by Agroscope aimed to understand the factors contributing to this variability and to find ways to better manage these intercropping systems[1]. The study involved a network of 28 farmers' fields planted with WOSR intercropped with various service plant mixtures. The farmers employed diverse practices regarding the specific composition of the service plant mixtures, pest management, and fertilization. The researchers observed significant variability in the growth of both oilseed rape and service plants during the fall. They identified that the main drivers of the service plant mixture's dry weight in late fall were the specific composition of the mixture and precipitation levels. Notably, the introduction of buckwheat in the service plant mixture enhanced its late fall biomass. One of the critical findings of the study was that oilseed rape grain yields varied widely, ranging from 0.4 to 5.0 t ha−1. In 75% of the fields, the yields were lower than the local reference. The primary reason for this was insect pest damage in the spring, exacerbated by the minimal use of insecticides and the lack of alternative pest management strategies. This aligns with earlier findings that chemical control of insect pests in oilseed rape is becoming increasingly difficult due to resistance and restrictive insecticide approvals in Europe[2]. The study suggests that understanding and managing pest pressure is crucial for improving yield stability in intercropping systems. Temperature also plays a significant role in WOSR yield variability. Previous research has shown that mean temperature in early winter is strongly linked to yield variation, with a rise in mean temperature leading to a decrease in yield[3]. This factor, combined with the variability in service plant growth and pest pressure, contributes to the challenges faced by farmers in achieving stable and high yields. Another aspect to consider is the impact of lodging, which negatively affects yield, seed quality, and harvestability in winter rapeseed. Lodging-induced yield losses can be mitigated by optimizing nitrogen application rates and planting densities[4]. This finding is relevant as it suggests that careful management of fertilization and planting density could help reduce yield losses in intercropping systems. Cover crops, such as those used in the intercropping mixtures, provide various benefits, including nitrogen accumulation and retention, weed suppression, and organic matter maintenance[5]. However, the performance of these cover crops can be highly variable depending on factors such as seeding mixtures, planting dates, and termination dates. The study by Agroscope highlights the importance of selecting the right service plant mixtures and managing them effectively to maximize their benefits. In conclusion, the study by Agroscope provides valuable insights into the factors contributing to yield variability in WOSR intercropped with service plants. By understanding the roles of service plant composition, precipitation, pest management, and temperature, farmers can better manage their intercropping systems to achieve more stable and resilient yields. The findings also underscore the need for integrated pest management strategies and careful optimization of fertilization and planting practices to mitigate the challenges associated with intercropping in temperate climates.

AgricultureSustainabilityPlant Science

References

Main Study

1) Determinants of oilseed rape-service plant intercropping performance variability across a farmers’ fields network in Western Switzerland

Published 12th July, 2024

https://doi.org/10.1007/s13593-024-00972-6

Related Studies

2) Effects of regional crop rotations on autumn insect pests in winter oilseed rape.

https://doi.org/10.1002/ps.7716

3) Yield instability of winter oilseed rape modulated by early winter temperature.

https://doi.org/10.1038/s41598-019-43461-7

4) Alteration in yield and oil quality traits of winter rapeseed by lodging at different planting density and nitrogen rates.

https://doi.org/10.1038/s41598-017-18734-8

5) Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

https://doi.org/10.1371/journal.pone.0129597


Related Articles

An unhandled error has occurred. Reload 🗙