The importance of genetic pod shatter resistance

Pod shatter resistance should be one of the first things on a grower’s mind when selecting the right OSR variety. This early choice combats the potential risk of losing seed just before harvest when the majority of the investment in the crop has already been made. The pod shatter resistance trait provides genetic security and helps protect that investment.

In the season of 2024, due to the weather in July the risk of pod shatter was not as high as it had been in previous years. This doesn’t alter the fact that at the time of varietal selection, we have no idea what the weather conditions are going to be 11 months down the line when the crop is at the most risk. Increasingly unpredictable UK weather systems mean we never know when the next high wind or unseasonably high rainfall will occur. It makes sense that growers protect themselves against the risk of significant yield loss from the start, by choosing a pod shatter resistant variety.

Limagrain tests their varieties every year using a lab-based technique where the force used to break the pods is measured in Newtons. This provides a robust quantifiable data set over multiple years. The pod shatter resistant varieties in some cases can require up to 3 x more force to break than non-pod shatter resistant varieties, making it far and away the most effective option for preventing pod shatter and limiting yield loss at harvest.

The effect of pod shatter on a crop can be observed in the field, The shelled out white pods are easy to spot, especially when the OSR volunteers appear after harvest. As the shattered seed germinates, the resulting increase in volunteer OSR has a secondary consequence. It creates a ‘green bridge’ for issues such as disease and pest’s and increasing the burden of weed control. This means that the initial pod loss doesn’t just impact the yield of the current crop. It directly impacts the next crop in the rotation, and possible future planting.

In OSR where margins are unquestionably tighter than ever, pod shatter resistance is key to profitability. Choosing a variety with genetic resistance can make a difference of around half a tonne per hectare at harvest. Success with OSR is increasingly contingent on grower’s mindset, as year on year growing it becomes more challenging and costly. This must now be viewed as a technical crop and as such varietal selection is key, the question I would pose to anyone looking to drill this Autumn is, why would you choose a variety without pod shatter resistance?

Ryan Kemp, Senior Trials Officer